Avatar of the Ozolith

Mutate {w/u}{u/b}{b/r}{r/g}{g/w}
Trample, Flying
Whenever this creature mutates, it gets your choice
of +X/+0 or +0/+X, where X is the number of times this creature has mutated.

Each non-Human creature card in your hand without mutate has mutate. It's mutate cost is equal
to it's mana cost reduced by X, where X is the number of times this creature has mutated.