Using a break to avoid extensive loop.

L2J_Mobius_3.0_Helios/dist/game/data/scripts/ai/others/SiegeGuards.java

@@ -118,6 +118,7 @@ public class SiegeGuards extends AbstractNpcAI
 								if (!pl.isInvisible() && !pl.isInvul()) // skip invisible players
 								{
 									addAttackPlayerDesire(npc, pl);
+									break; // no need to search more
 								}
 							}
 						}