The lore of Ready Player Earn revolves around alchemy, and Zosimir is the chief alchemist. Here he is in his cave. He had this to say: " I spend my days in a medieval city in a quiet town where I scavenge the countryside and explore dangerous dungeons to find rare plants, metals, chemicals, and body parts to mix for my potions. Assassins love my tasteless and colorless drops that turn wine into instant death. The clergy comes for my healing medicines, though I know many apply them secretly while taking donations meant to guarantee answered prayers from the gods. Archers purchase a poison to dip their arrowheads, and I also make an antidote for when they inevitably poison themselves. This business has been profitable for me, and I have anonymously purchased a tavern, temple, bread stand, barn, and stable to control my town in secrecy from my cavernous laboratory."

This appears on page viii of the book Ready Player Earn.