Souvenir Snatcher

Souvenir Snatcher

Creature - Bird | Power/Toughness: 4 / 4 (CMC 5)
Mutate (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Flying
Whenever this creature mutates, gain control of target noncreature artifact.