Wizard Number Zero 

Nikolai thought his greatest challenge as a member of Genesis, a group fighting calamity, would be living in the shadow of his best friend, Elras. That is, until Elras breaks the cardinal rule: never use magic to harm another. Years of friendship and magical knowledge are erased from Elras’ memory to keep him from hurting others, and Nikolai is assigned to watch over him. But then, they find out that Elras can cast magic without a wand, and more mysterious clues about his dismissal come to light. Nothing comes easy for this duo!