Falaxi, Prowler of The Peaks

Mutate {3}{w}{u}{r}(When you cast this spell
for its mutate cost, put it under or over target
non-Human creature you own. They mutate
into the creature on top and have all abilities
of the creatures under it.)
—
Flash
Whenever this creature mutates copy target
instant if it targets a player or target
sorcery if it target a permanent.