Veruti:
Alchemy can only be learned by Ertheia from the Spirit Realm.
It requires arduous training if one is to produce rare items, so you need to have at least undergone 1st Liberation in order to understand the basics of it!
Alchemy is divided into Combination and Transmutation. The Alchemy Cube is used in Combination while Transmutation allows you to transmute a variety of rare items. There's one more category, but I'll tell you about it later when the time is right. Hehe!