Support for drop groups.

L2J_Mobius_01.0_Ertheia/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_01.0_Ertheia/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_01.0_Ertheia/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_01.0_Ertheia/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_01.0_Ertheia/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_01.0_Ertheia/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_02.5_Underground/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_02.5_Underground/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_02.5_Underground/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_02.5_Underground/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_02.5_Underground/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_02.5_Underground/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_03.0_Helios/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_03.0_Helios/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_03.0_Helios/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_03.0_Helios/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_03.0_Helios/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_03.0_Helios/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_04.0_GrandCrusade/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_04.0_GrandCrusade/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_04.0_GrandCrusade/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_04.0_GrandCrusade/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_04.0_GrandCrusade/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_04.0_GrandCrusade/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_05.0_Salvation/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_05.0_Salvation/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_05.0_Salvation/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_05.0_Salvation/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_05.0_Salvation/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_05.0_Salvation/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_05.5_EtinasFate/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_05.5_EtinasFate/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_05.5_EtinasFate/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_05.5_EtinasFate/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_05.5_EtinasFate/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_05.5_EtinasFate/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_06.0_Fafurion/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_06.0_Fafurion/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_06.0_Fafurion/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_06.0_Fafurion/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_06.0_Fafurion/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_06.0_Fafurion/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_07.0_PreludeOfWar/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_07.0_PreludeOfWar/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_07.0_PreludeOfWar/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_07.0_PreludeOfWar/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_07.0_PreludeOfWar/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_07.0_PreludeOfWar/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_08.2_Homunculus/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_08.2_Homunculus/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_08.2_Homunculus/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_08.2_Homunculus/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseInteger(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_08.2_Homunculus/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_08.2_Homunculus/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_09.2_ReturnOfTheQueenAnt/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_09.2_ReturnOfTheQueenAnt/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_09.2_ReturnOfTheQueenAnt/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_09.2_ReturnOfTheQueenAnt/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseInteger(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_09.2_ReturnOfTheQueenAnt/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_09.2_ReturnOfTheQueenAnt/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_10.1_MasterClass/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_10.1_MasterClass/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_10.1_MasterClass/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_10.1_MasterClass/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseInteger(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_10.1_MasterClass/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_10.1_MasterClass/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_10.2_MasterClass/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_10.2_MasterClass/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_10.2_MasterClass/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_10.2_MasterClass/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseInteger(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_10.2_MasterClass/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -107,6 +108,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -649,12 +651,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -673,6 +685,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -685,11 +702,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -721,7 +928,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -776,20 +983,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_10.2_MasterClass/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_CT_2.4_Epilogue/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -35,6 +35,7 @@ import org.l2jmobius.gameserver.model.WorldObject;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.network.serverpackets.NpcHtmlMessage;
@@ -206,12 +207,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -228,13 +230,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_CT_2.4_Epilogue/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.Spawn;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -102,6 +103,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_CT_2.4_Epilogue/dist/game/data/xsd/npcs.xsd

@@ -13,7 +13,67 @@
 			<xs:element name="ai" type="aiType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="collision" type="collisionType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="corpseTime" type="xs:nonNegativeInteger" minOccurs="0" maxOccurs="1" />
-			<xs:element name="dropLists" type="dropListsType" minOccurs="0" maxOccurs="1" />
+			<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
+				<xs:complexType>
+					<xs:sequence>
+						<xs:element name="drop" minOccurs="0">
+							<xs:complexType>
+								<xs:sequence>
+									<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:simpleContent>
+												<xs:extension base="xs:string">
+													<xs:attribute type="xs:int" name="id" use="required"/>
+													<xs:attribute type="xs:long" name="min" use="required"/>
+													<xs:attribute type="xs:long" name="max" use="required"/>
+													<xs:attribute type="xs:double" name="chance" use="required"/>
+												</xs:extension>
+											</xs:simpleContent>
+										</xs:complexType>
+									</xs:element>
+									<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:sequence>
+												<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+													<xs:complexType>
+														<xs:simpleContent>
+															<xs:extension base="xs:string">
+																<xs:attribute type="xs:int" name="id" use="required"/>
+																<xs:attribute type="xs:long" name="min" use="required"/>
+																<xs:attribute type="xs:long" name="max" use="required"/>
+																<xs:attribute type="xs:double" name="chance" use="required"/>
+															</xs:extension>
+														</xs:simpleContent>
+													</xs:complexType>
+												</xs:element>
+											</xs:sequence>
+											<xs:attribute type="xs:double" name="chance" use="optional"/>
+										</xs:complexType>
+									</xs:element>
+								</xs:sequence>
+							</xs:complexType>
+						</xs:element>
+						<xs:element name="spoil" minOccurs="0">
+							<xs:complexType>
+								<xs:sequence>
+									<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:simpleContent>
+												<xs:extension base="xs:string">
+													<xs:attribute type="xs:int" name="id" use="optional"/>
+													<xs:attribute type="xs:long" name="min" use="optional"/>
+													<xs:attribute type="xs:long" name="max" use="optional"/>
+													<xs:attribute type="xs:double" name="chance" use="optional"/>
+												</xs:extension>
+											</xs:simpleContent>
+										</xs:complexType>
+									</xs:element>
+								</xs:sequence>
+							</xs:complexType>
+						</xs:element>
+					</xs:sequence>
+				</xs:complexType>
+			</xs:element>
 			<xs:element name="equipment" type="equipmentType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="exCrtEffect" type="xs:boolean" minOccurs="0" maxOccurs="1" />
 			<xs:element name="parameters" type="parametersType" minOccurs="0" maxOccurs="1" />

L2J_Mobius_CT_2.4_Epilogue/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -43,6 +43,7 @@ import org.l2jmobius.gameserver.enums.DropType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.MinionHolder;
 import org.l2jmobius.gameserver.model.holders.SkillHolder;
@@ -99,6 +100,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -456,24 +458,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -630,10 +662,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_CT_2.4_Epilogue/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -34,6 +34,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -98,6 +99,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private double _collisionRadiusGrown;
@@ -588,12 +590,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -612,6 +624,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -624,11 +641,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -660,7 +867,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -715,20 +922,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_CT_2.4_Epilogue/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_CT_2.6_HighFive/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -35,6 +35,7 @@ import org.l2jmobius.gameserver.model.WorldObject;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.network.serverpackets.NpcHtmlMessage;
@@ -206,12 +207,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -228,13 +230,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_CT_2.6_HighFive/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.Spawn;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -102,6 +103,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_CT_2.6_HighFive/dist/game/data/xsd/npcs.xsd

@@ -13,7 +13,67 @@
 			<xs:element name="ai" type="aiType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="collision" type="collisionType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="corpseTime" type="xs:nonNegativeInteger" minOccurs="0" maxOccurs="1" />
-			<xs:element name="dropLists" type="dropListsType" minOccurs="0" maxOccurs="1" />
+			<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
+				<xs:complexType>
+					<xs:sequence>
+						<xs:element name="drop" minOccurs="0">
+							<xs:complexType>
+								<xs:sequence>
+									<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:simpleContent>
+												<xs:extension base="xs:string">
+													<xs:attribute type="xs:int" name="id" use="required"/>
+													<xs:attribute type="xs:long" name="min" use="required"/>
+													<xs:attribute type="xs:long" name="max" use="required"/>
+													<xs:attribute type="xs:double" name="chance" use="required"/>
+												</xs:extension>
+											</xs:simpleContent>
+										</xs:complexType>
+									</xs:element>
+									<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:sequence>
+												<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+													<xs:complexType>
+														<xs:simpleContent>
+															<xs:extension base="xs:string">
+																<xs:attribute type="xs:int" name="id" use="required"/>
+																<xs:attribute type="xs:long" name="min" use="required"/>
+																<xs:attribute type="xs:long" name="max" use="required"/>
+																<xs:attribute type="xs:double" name="chance" use="required"/>
+															</xs:extension>
+														</xs:simpleContent>
+													</xs:complexType>
+												</xs:element>
+											</xs:sequence>
+											<xs:attribute type="xs:double" name="chance" use="optional"/>
+										</xs:complexType>
+									</xs:element>
+								</xs:sequence>
+							</xs:complexType>
+						</xs:element>
+						<xs:element name="spoil" minOccurs="0">
+							<xs:complexType>
+								<xs:sequence>
+									<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+										<xs:complexType>
+											<xs:simpleContent>
+												<xs:extension base="xs:string">
+													<xs:attribute type="xs:int" name="id" use="optional"/>
+													<xs:attribute type="xs:long" name="min" use="optional"/>
+													<xs:attribute type="xs:long" name="max" use="optional"/>
+													<xs:attribute type="xs:double" name="chance" use="optional"/>
+												</xs:extension>
+											</xs:simpleContent>
+										</xs:complexType>
+									</xs:element>
+								</xs:sequence>
+							</xs:complexType>
+						</xs:element>
+					</xs:sequence>
+				</xs:complexType>
+			</xs:element>
 			<xs:element name="equipment" type="equipmentType" minOccurs="0" maxOccurs="1" />
 			<xs:element name="exCrtEffect" type="xs:boolean" minOccurs="0" maxOccurs="1" />
 			<xs:element name="parameters" type="parametersType" minOccurs="0" maxOccurs="1" />

L2J_Mobius_CT_2.6_HighFive/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -43,6 +43,7 @@ import org.l2jmobius.gameserver.enums.DropType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.MinionHolder;
 import org.l2jmobius.gameserver.model.holders.SkillHolder;
@@ -99,6 +100,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -456,24 +458,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -630,10 +662,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_CT_2.6_HighFive/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -34,6 +34,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -98,6 +99,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private double _collisionRadiusGrown;
@@ -588,12 +590,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -612,6 +624,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -624,11 +641,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -660,7 +867,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -715,20 +922,82 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		return calculatedDrops;
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_CT_2.6_HighFive/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_Classic_2.0_Saviors/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_Classic_2.0_Saviors/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_Classic_2.0_Saviors/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_Classic_2.0_Saviors/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_Classic_2.0_Saviors/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -108,6 +109,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -650,12 +652,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -674,6 +686,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -686,11 +703,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -722,7 +929,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -777,7 +984,10 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		if (Config.VIP_SYSTEM_ENABLED && (dropType == DropType.DROP))
@@ -840,7 +1050,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		{
 			return null;
 		}
-		return calculateDrop(dropItem, victim, killer);
+		return calculateUngroupedDrop(dropItem, victim, killer);
 	}
 	
 	private double calculateLevelGapChanceToDrop(DropHolder dropItem, int levelDifference)
@@ -858,13 +1068,72 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_Classic_2.0_Saviors/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_Classic_2.1_Zaken/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_Classic_2.1_Zaken/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_Classic_2.1_Zaken/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_Classic_2.1_Zaken/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)

L2J_Mobius_Classic_2.1_Zaken/java/org/l2jmobius/gameserver/model/actor/templates/NpcTemplate.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.enums.Race;
 import org.l2jmobius.gameserver.enums.Sex;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.Creature;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.holders.ItemHolder;
 import org.l2jmobius.gameserver.model.interfaces.IIdentifiable;
@@ -108,6 +109,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	private Map<AISkillScope, List<Skill>> _aiSkillLists;
 	private Set<Integer> _clans;
 	private Set<Integer> _ignoreClanNpcIds;
+	private List<DropGroupHolder> _dropGroups;
 	private List<DropHolder> _dropListDeath;
 	private List<DropHolder> _dropListSpoil;
 	private float _collisionRadiusGrown;
@@ -650,12 +652,22 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_ignoreClanNpcIds = ignoreClanNpcIds != null ? Collections.unmodifiableSet(ignoreClanNpcIds) : null;
 	}
 	
+	public void removeDropGroups()
+	{
+		_dropGroups = null;
+	}
+	
 	public void removeDrops()
 	{
 		_dropListDeath = null;
 		_dropListSpoil = null;
 	}
 	
+	public void setDropGroups(List<DropGroupHolder> groups)
+	{
+		_dropGroups = groups;
+	}
+	
 	public void addDrop(DropHolder dropHolder)
 	{
 		if (_dropListDeath == null)
@@ -674,6 +686,11 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		_dropListSpoil.add(dropHolder);
 	}
 	
+	public List<DropGroupHolder> getDropGroups()
+	{
+		return _dropGroups;
+	}
+	
 	public List<DropHolder> getDropList()
 	{
 		return _dropListDeath;
@@ -686,11 +703,201 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	
 	public List<ItemHolder> calculateDrops(DropType dropType, Creature victim, Creature killer)
 	{
-		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
+		if (dropType == DropType.DROP)
-		if (dropList == null)
 		{
-			return null;
+			// calculate group drops
+			List<ItemHolder> groupDrops = null;
+			if (_dropGroups != null)
+			{
+				groupDrops = calculateGroupDrops(victim, killer);
+			}
+			
+			// calculate ungrouped drops
+			List<ItemHolder> ungroupedDrops = null;
+			if (_dropListDeath != null)
+			{
+				ungroupedDrops = calculateUngroupedDrops(dropType, victim, killer);
+			}
+			
+			// return results
+			if ((groupDrops != null) && (ungroupedDrops != null))
+			{
+				groupDrops.addAll(ungroupedDrops);
+				ungroupedDrops.clear();
+				return groupDrops;
+			}
+			if (groupDrops != null)
+			{
+				return groupDrops;
+			}
+			if (ungroupedDrops != null)
+			{
+				return ungroupedDrops;
+			}
 		}
+		else if ((dropType == DropType.SPOIL) && (_dropListSpoil != null))
+		{
+			return calculateUngroupedDrops(dropType, victim, killer);
+		}
+		
+		// no drops
+		return null;
+	}
+	
+	private List<ItemHolder> calculateGroupDrops(Creature victim, Creature killer)
+	{
+		// level difference calculations
+		final int levelDifference = victim.getLevel() - killer.getLevel();
+		final double levelGapChanceToDropAdena = Util.map(levelDifference, -Config.DROP_ADENA_MAX_LEVEL_DIFFERENCE, -Config.DROP_ADENA_MIN_LEVEL_DIFFERENCE, Config.DROP_ADENA_MIN_LEVEL_GAP_CHANCE, 100d);
+		final double levelGapChanceToDrop = Util.map(levelDifference, -Config.DROP_ITEM_MAX_LEVEL_DIFFERENCE, -Config.DROP_ITEM_MIN_LEVEL_DIFFERENCE, Config.DROP_ITEM_MIN_LEVEL_GAP_CHANCE, 100d);
+		
+		int dropOccurrenceCounter = victim.isRaid() ? Config.DROP_MAX_OCCURRENCES_RAIDBOSS : Config.DROP_MAX_OCCURRENCES_NORMAL;
+		List<ItemHolder> calculatedDrops = null;
+		for (DropGroupHolder group : _dropGroups)
+		{
+			if (dropOccurrenceCounter <= 0)
+			{
+				break;
+			}
+			
+			double groupRate = 1;
+			final List<DropHolder> groupDrops = group.getDropList();
+			for (DropHolder dropItem : groupDrops)
+			{
+				final int itemId = dropItem.getItemId();
+				final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+				final boolean champion = victim.isChampion();
+				
+				// chance
+				double rateChance = 1;
+				final Float itemChance = Config.RATE_DROP_CHANCE_BY_ID.get(itemId);
+				if (itemChance != null)
+				{
+					if (itemChance == 0)
+					{
+						continue;
+					}
+					
+					rateChance *= itemChance;
+					if (champion && (itemId == Inventory.ADENA_ID))
+					{
+						rateChance *= Config.CHAMPION_ADENAS_REWARDS_CHANCE;
+					}
+				}
+				else if (item.hasExImmediateEffect())
+				{
+					rateChance *= Config.RATE_HERB_DROP_CHANCE_MULTIPLIER;
+				}
+				else if (victim.isRaid())
+				{
+					rateChance *= Config.RATE_RAID_DROP_CHANCE_MULTIPLIER;
+				}
+				else
+				{
+					rateChance *= Config.RATE_DEATH_DROP_CHANCE_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_CHANCE : 1);
+				}
+				
+				// premium chance
+				if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+				{
+					if (Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId) != null)
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE_BY_ID.get(itemId);
+					}
+					else if (item.hasExImmediateEffect())
+					{
+						// TODO: Premium herb chance? :)
+					}
+					else if (victim.isRaid())
+					{
+						// TODO: Premium raid chance? :)
+					}
+					else
+					{
+						rateChance *= Config.PREMIUM_RATE_DROP_CHANCE;
+					}
+				}
+				
+				// keep lowest to avoid chance by id configuration conflicts
+				groupRate = Math.min(groupRate, rateChance);
+			}
+			
+			if ((Rnd.nextDouble() * 100) < (group.getChance() * groupRate))
+			{
+				double totalChance = 0; // total group chance is 100
+				final double dropChance = Rnd.nextDouble() * 100;
+				GROUP_DROP: for (DropHolder dropItem : groupDrops)
+				{
+					if (dropOccurrenceCounter <= 0)
+					{
+						break;
+					}
+					
+					// calculate if item will drop
+					totalChance += dropItem.getChance();
+					if (dropChance >= totalChance)
+					{
+						continue;
+					}
+					
+					// check level gap that may prevent to drop item
+					if ((Rnd.nextDouble() * 100) > (dropItem.getItemId() == Inventory.ADENA_ID ? levelGapChanceToDropAdena : levelGapChanceToDrop))
+					{
+						continue;
+					}
+					
+					// create the drop
+					final ItemHolder drop = calculateGroupDrop(dropItem, victim, killer);
+					
+					// create list
+					if (calculatedDrops == null)
+					{
+						calculatedDrops = new ArrayList<>(dropOccurrenceCounter);
+					}
+					
+					// finally
+					if (group.getChance() < 100)
+					{
+						dropOccurrenceCounter--;
+					}
+					calculatedDrops.add(drop);
+					
+					// no more drops from this group
+					break GROUP_DROP;
+				}
+			}
+		}
+		
+		// champion extra drop
+		if (victim.isChampion())
+		{
+			if ((victim.getLevel() < killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_LOWER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			if ((victim.getLevel() > killer.getLevel()) && (Rnd.get(100) < Config.CHAMPION_REWARD_HIGHER_LEVEL_ITEM_CHANCE))
+			{
+				return calculatedDrops;
+			}
+			
+			// create list
+			if (calculatedDrops == null)
+			{
+				calculatedDrops = new ArrayList<>();
+			}
+			
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
+		}
+		
+		return calculatedDrops;
+	}
+	
+	private List<ItemHolder> calculateUngroupedDrops(DropType dropType, Creature victim, Creature killer)
+	{
+		final List<DropHolder> dropList = dropType == DropType.SPOIL ? _dropListSpoil : _dropListDeath;
 		
 		// level difference calculations
 		final int levelDifference = victim.getLevel() - killer.getLevel();
@@ -722,7 +929,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				}
 				
 				// calculate chances
-				final ItemHolder drop = calculateDrop(dropItem, victim, killer);
+				final ItemHolder drop = calculateUngroupedDrop(dropItem, victim, killer);
 				if (drop == null)
 				{
 					continue;
@@ -777,7 +984,10 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 				calculatedDrops = new ArrayList<>();
 			}
 			
-			calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			if (!calculatedDrops.containsAll(Config.CHAMPION_REWARD_ITEMS))
+			{
+				calculatedDrops.addAll(Config.CHAMPION_REWARD_ITEMS);
+			}
 		}
 		
 		if (Config.VIP_SYSTEM_ENABLED && (dropType == DropType.DROP))
@@ -840,7 +1050,7 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 		{
 			return null;
 		}
-		return calculateDrop(dropItem, victim, killer);
+		return calculateUngroupedDrop(dropItem, victim, killer);
 	}
 	
 	private double calculateLevelGapChanceToDrop(DropHolder dropItem, int levelDifference)
@@ -858,13 +1068,72 @@ public class NpcTemplate extends CreatureTemplate implements IIdentifiable
 	}
 	
 	/**
-	 * All item drop chance calculations are done by this method.
 	 * @param dropItem
 	 * @param victim
 	 * @param killer
 	 * @return ItemHolder
 	 */
-	private ItemHolder calculateDrop(DropHolder dropItem, Creature victim, Creature killer)
+	private ItemHolder calculateGroupDrop(DropHolder dropItem, Creature victim, Creature killer)
+	{
+		final int itemId = dropItem.getItemId();
+		final ItemTemplate item = ItemTable.getInstance().getTemplate(itemId);
+		final boolean champion = victim.isChampion();
+		
+		// calculate amount
+		double rateAmount = 1;
+		if (Config.RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+		{
+			rateAmount *= Config.RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			if (champion && (itemId == Inventory.ADENA_ID))
+			{
+				rateAmount *= Config.CHAMPION_ADENAS_REWARDS_AMOUNT;
+			}
+		}
+		else if (item.hasExImmediateEffect())
+		{
+			rateAmount *= Config.RATE_HERB_DROP_AMOUNT_MULTIPLIER;
+		}
+		else if (victim.isRaid())
+		{
+			rateAmount *= Config.RATE_RAID_DROP_AMOUNT_MULTIPLIER;
+		}
+		else
+		{
+			rateAmount *= Config.RATE_DEATH_DROP_AMOUNT_MULTIPLIER * (champion ? Config.CHAMPION_REWARDS_AMOUNT : 1);
+		}
+		
+		// premium amount
+		if (Config.PREMIUM_SYSTEM_ENABLED && (killer.getActingPlayer() != null) && killer.getActingPlayer().hasPremiumStatus())
+		{
+			if (Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId) != null)
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT_BY_ID.get(itemId);
+			}
+			else if (item.hasExImmediateEffect())
+			{
+				// TODO: Premium herb amount? :)
+			}
+			else if (victim.isRaid())
+			{
+				// TODO: Premium raid amount? :)
+			}
+			else
+			{
+				rateAmount *= Config.PREMIUM_RATE_DROP_AMOUNT;
+			}
+		}
+		
+		// finally
+		return new ItemHolder(itemId, (long) (Rnd.get(dropItem.getMin(), dropItem.getMax()) * rateAmount));
+	}
+	
+	/**
+	 * @param dropItem
+	 * @param victim
+	 * @param killer
+	 * @return ItemHolder
+	 */
+	private ItemHolder calculateUngroupedDrop(DropHolder dropItem, Creature victim, Creature killer)
 	{
 		switch (dropItem.getDropType())
 		{

L2J_Mobius_Classic_2.1_Zaken/java/org/l2jmobius/gameserver/model/holders/DropGroupHolder.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.l2jmobius.gameserver.model.holders;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author Mobius
+ */
+public class DropGroupHolder
+{
+	private final List<DropHolder> _dropList = new ArrayList<>();
+	private final double _chance;
+	
+	public DropGroupHolder(double chance)
+	{
+		_chance = chance;
+	}
+	
+	public List<DropHolder> getDropList()
+	{
+		return _dropList;
+	}
+	
+	public void addDrop(DropHolder holder)
+	{
+		_dropList.add(holder);
+	}
+	
+	public double getChance()
+	{
+		return _chance;
+	}
+}

L2J_Mobius_Classic_2.2_Antharas/dist/game/data/scripts/handlers/bypasshandlers/NpcViewMod.java

@@ -37,6 +37,7 @@ import org.l2jmobius.gameserver.model.actor.Attackable;
 import org.l2jmobius.gameserver.model.actor.Creature;
 import org.l2jmobius.gameserver.model.actor.Npc;
 import org.l2jmobius.gameserver.model.actor.Player;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -326,12 +327,13 @@ public class NpcViewMod implements IBypassHandler
 	private static String getDropListButtons(Npc npc)
 	{
 		final StringBuilder sb = new StringBuilder();
+		final List<DropGroupHolder> dropListGroups = npc.getTemplate().getDropGroups();
 		final List<DropHolder> dropListDeath = npc.getTemplate().getDropList();
 		final List<DropHolder> dropListSpoil = npc.getTemplate().getSpoilList();
-		if ((dropListDeath != null) || (dropListSpoil != null))
+		if ((dropListGroups != null) || (dropListDeath != null) || (dropListSpoil != null))
 		{
 			sb.append("<table width=275 cellpadding=0 cellspacing=0><tr>");
-			if (dropListDeath != null)
+			if ((dropListGroups != null) || (dropListDeath != null))
 			{
 				sb.append("<td align=center><button value=\"Show Drop\" width=100 height=25 action=\"bypass NpcViewMod dropList DROP " + npc.getObjectId() + "\" back=\"L2UI_CT1.Button_DF_Calculator_Down\" fore=\"L2UI_CT1.Button_DF_Calculator\"></td>");
 			}
@@ -348,13 +350,40 @@ public class NpcViewMod implements IBypassHandler
 	
 	private void sendNpcDropList(Player player, Npc npc, DropType dropType, int pageValue)
 	{
-		final List<DropHolder> templateList = dropType == DropType.SPOIL ? npc.getTemplate().getSpoilList() : npc.getTemplate().getDropList();
+		List<DropHolder> dropList = null;
-		if (templateList == null)
+		if (dropType == DropType.SPOIL)
+		{
+			dropList = new ArrayList<>(npc.getTemplate().getSpoilList());
+		}
+		else
+		{
+			final List<DropHolder> drops = npc.getTemplate().getDropList();
+			if (drops != null)
+			{
+				dropList = new ArrayList<>(drops);
+			}
+			final List<DropGroupHolder> dropGroups = npc.getTemplate().getDropGroups();
+			if (dropGroups != null)
+			{
+				if (dropList == null)
+				{
+					dropList = new ArrayList<>();
+				}
+				for (DropGroupHolder dropGroup : dropGroups)
+				{
+					final double chance = dropGroup.getChance() / 100;
+					for (DropHolder dropHolder : dropGroup.getDropList())
+					{
+						dropList.add(new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+					}
+				}
+			}
+		}
+		if (dropList == null)
 		{
 			return;
 		}
 		
-		final List<DropHolder> dropList = new ArrayList<>(templateList);
 		Collections.sort(dropList, (d1, d2) -> Integer.valueOf(d1.getItemId()).compareTo(Integer.valueOf(d2.getItemId())));
 		
 		int pages = dropList.size() / DROP_LIST_ITEMS_PER_PAGE;

L2J_Mobius_Classic_2.2_Antharas/dist/game/data/scripts/handlers/communityboard/DropSearchBoard.java

@@ -36,6 +36,7 @@ import org.l2jmobius.gameserver.handler.CommunityBoardHandler;
 import org.l2jmobius.gameserver.handler.IParseBoardHandler;
 import org.l2jmobius.gameserver.model.actor.Player;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.item.ItemTemplate;
 import org.l2jmobius.gameserver.model.itemcontainer.Inventory;
@@ -104,6 +105,17 @@ public class DropSearchBoard implements IParseBoardHandler
 	
 	private void buildDropIndex()
 	{
+		NpcData.getInstance().getTemplates(npc -> npc.getDropGroups() != null).forEach(npcTemplate ->
+		{
+			for (DropGroupHolder dropGroup : npcTemplate.getDropGroups())
+			{
+				final double chance = dropGroup.getChance() / 100;
+				for (DropHolder dropHolder : dropGroup.getDropList())
+				{
+					addToDropList(npcTemplate, new DropHolder(dropHolder.getDropType(), dropHolder.getItemId(), dropHolder.getMin(), dropHolder.getMax(), dropHolder.getChance() * chance));
+				}
+			}
+		});
 		NpcData.getInstance().getTemplates(npc -> npc.getDropList() != null).forEach(npcTemplate ->
 		{
 			for (DropHolder dropHolder : npcTemplate.getDropList())

L2J_Mobius_Classic_2.2_Antharas/dist/game/data/xsd/npcs.xsd

@@ -1,16 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
-	<xs:complexType name="dropListItem">
-		<xs:attribute name="id" type="xs:positiveInteger" use="required" />
-		<xs:attribute name="min" type="xs:nonNegativeInteger" />
-		<xs:attribute name="max" type="xs:positiveInteger" />
-		<xs:attribute name="chance" type="xs:decimal" />
-	</xs:complexType>
-	<xs:complexType name="dropList">
-		<xs:choice minOccurs="1" maxOccurs="unbounded">
-			<xs:element name="item" type="dropListItem" />
-		</xs:choice>
-	</xs:complexType>
 	<xs:element name="list">
 		<xs:complexType>
 			<xs:sequence>
@@ -260,11 +249,81 @@
 							</xs:element>
 							<xs:element name="dropLists" minOccurs="0" maxOccurs="1">
 								<xs:complexType>
-									<xs:all>
+									<xs:sequence>
-										<xs:element name="drop" type="dropList" minOccurs="0" maxOccurs="1" />
+										<xs:element name="drop" minOccurs="0">
-										<xs:element name="spoil" type="dropList" minOccurs="0" maxOccurs="1" />
+											<xs:complexType>
-										<xs:element name="lucky" type="dropList" minOccurs="0" maxOccurs="1" />
+												<xs:sequence>
-									</xs:all>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="required"/>
+																	<xs:attribute type="xs:long" name="min" use="required"/>
+																	<xs:attribute type="xs:long" name="max" use="required"/>
+																	<xs:attribute type="xs:double" name="chance" use="required"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+													<xs:element name="group" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:sequence>
+																<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+																	<xs:complexType>
+																		<xs:simpleContent>
+																			<xs:extension base="xs:string">
+																				<xs:attribute type="xs:int" name="id" use="required"/>
+																				<xs:attribute type="xs:long" name="min" use="required"/>
+																				<xs:attribute type="xs:long" name="max" use="required"/>
+																				<xs:attribute type="xs:double" name="chance" use="required"/>
+																			</xs:extension>
+																		</xs:simpleContent>
+																	</xs:complexType>
+																</xs:element>
+															</xs:sequence>
+															<xs:attribute type="xs:double" name="chance" use="optional"/>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="spoil" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+										<xs:element name="lucky" minOccurs="0">
+											<xs:complexType>
+												<xs:sequence>
+													<xs:element name="item" maxOccurs="unbounded" minOccurs="0">
+														<xs:complexType>
+															<xs:simpleContent>
+																<xs:extension base="xs:string">
+																	<xs:attribute type="xs:int" name="id" use="optional"/>
+																	<xs:attribute type="xs:long" name="min" use="optional"/>
+																	<xs:attribute type="xs:long" name="max" use="optional"/>
+																	<xs:attribute type="xs:double" name="chance" use="optional"/>
+																</xs:extension>
+															</xs:simpleContent>
+														</xs:complexType>
+													</xs:element>
+												</xs:sequence>
+											</xs:complexType>
+										</xs:element>
+									</xs:sequence>
 								</xs:complexType>
 							</xs:element>
 							<xs:element name="collision" minOccurs="0" maxOccurs="1">

L2J_Mobius_Classic_2.2_Antharas/java/org/l2jmobius/gameserver/data/xml/NpcData.java

@@ -46,6 +46,7 @@ import org.l2jmobius.gameserver.enums.MpRewardType;
 import org.l2jmobius.gameserver.model.StatSet;
 import org.l2jmobius.gameserver.model.actor.templates.NpcTemplate;
 import org.l2jmobius.gameserver.model.effects.EffectType;
+import org.l2jmobius.gameserver.model.holders.DropGroupHolder;
 import org.l2jmobius.gameserver.model.holders.DropHolder;
 import org.l2jmobius.gameserver.model.skill.Skill;
 
@@ -100,6 +101,7 @@ public class NpcData implements IXmlReader
 						Set<Integer> clans = null;
 						Set<Integer> ignoreClanNpcIds = null;
 						List<DropHolder> dropLists = null;
+						List<DropGroupHolder> dropGroups = null;
 						set.set("id", npcId);
 						set.set("displayId", parseInteger(attrs, "displayId"));
 						set.set("level", parseByte(attrs, "level"));
@@ -436,24 +438,54 @@ public class NpcData implements IXmlReader
 										
 										if (dropType != null)
 										{
-											if (dropLists == null)
-											{
-												dropLists = new ArrayList<>();
-											}
-											
 											for (Node dropNode = dropListsNode.getFirstChild(); dropNode != null; dropNode = dropNode.getNextSibling())
 											{
-												final NamedNodeMap dropAttrs = dropNode.getAttributes();
+												final String nodeName = dropNode.getNodeName();
-												if ("item".equalsIgnoreCase(dropNode.getNodeName()))
+												if (nodeName.equalsIgnoreCase("group"))
 												{
-													final DropHolder dropItem = new DropHolder(dropType, parseInteger(dropAttrs, "id"), parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance"));
+													if (dropGroups == null)
-													if (ItemTable.getInstance().getTemplate(parseInteger(dropAttrs, "id")) == null)
 													{
-														LOGGER.warning("DropListItem: Could not find item with id " + parseInteger(dropAttrs, "id") + ".");
+														dropGroups = new ArrayList<>();
+													}
+													
+													final DropGroupHolder group = new DropGroupHolder(parseDouble(dropNode.getAttributes(), "chance"));
+													for (Node groupNode = dropNode.getFirstChild(); groupNode != null; groupNode = groupNode.getNextSibling())
+													{
+														if (groupNode.getNodeName().equalsIgnoreCase("item"))
+														{
+															final NamedNodeMap groupAttrs = groupNode.getAttributes();
+															final int itemId = parseInteger(groupAttrs, "id");
+															
+															if (ItemTable.getInstance().getTemplate(itemId) == null)
+															{
+																LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
+															}
+															else
+															{
+																group.addDrop(new DropHolder(dropType, itemId, parseLong(groupAttrs, "min"), parseLong(groupAttrs, "max"), parseDouble(groupAttrs, "chance")));
+															}
+														}
+													}
+													
+													dropGroups.add(group);
+												}
+												else if (nodeName.equalsIgnoreCase("item"))
+												{
+													if (dropLists == null)
+													{
+														dropLists = new ArrayList<>();
+													}
+													
+													final NamedNodeMap dropAttrs = dropNode.getAttributes();
+													final int itemId = parseInteger(dropAttrs, "id");
+													
+													if (ItemTable.getInstance().getTemplate(itemId) == null)
+													{
+														LOGGER.warning("DropListItem: Could not find item with id " + itemId + ".");
 													}
 													else
 													{
-														dropLists.add(dropItem);
+														dropLists.add(new DropHolder(dropType, itemId, parseLong(dropAttrs, "min"), parseLong(dropAttrs, "max"), parseDouble(dropAttrs, "chance")));
 													}
 												}
 											}
@@ -612,10 +644,21 @@ public class NpcData implements IXmlReader
 						template.setClans(clans);
 						template.setIgnoreClanNpcIds(ignoreClanNpcIds);
 						
+						// Clean old drop groups.
+						template.removeDropGroups();
+						
+						// Set new drop groups.
+						if (dropGroups != null)
+						{
+							template.setDropGroups(dropGroups);
+						}
+						
+						// Clean old drop lists.
+						template.removeDrops();
+						
+						// Set new drop lists.
 						if (dropLists != null)
 						{
-							template.removeDrops();
-							
 							// Drops are sorted by chance (high to low).
 							Collections.sort(dropLists, (d1, d2) -> Double.valueOf(d2.getChance()).compareTo(Double.valueOf(d1.getChance())));
 							for (DropHolder dropHolder : dropLists)