Ayigen, Unfractured Crystal

Traverse —Whenever Ayigen, Unfractured Crystal enters or leaves the battlefield, you may return target instant or sorcery spell from your graveyard to your hand.
Spells you cast that target Ayigen have rebound. (Exile the spell as it resolves if you cast it from your hand. At the beginning of your next upkeep, you may cast that card from exile without paying its mana