Bren, Prodigal Pyromancer

Bren, Prodigal Pyromancer enters the battlefield with four sanity counters on him.

Magecraft — Whenever you cast or copy an instant or sorcery spell, Bren deals 1 damage to each other creature and you may remove a sanity counter from him. Then if Bren has no sanity counters on him, exile Bren and return him to the battlefield transformed at the beginning of the next end step.