King Caesar, Ancient Guardian - Huntmaster Liger (IKO-370) - Ikoria: Lair of Behemoths / King Caesar, Ancient Guardian (Borderless)

Mutate {2} (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.)
Whenever this creature mutates, other creatures you control get +X/+X until end of turn, where X is the number of times this creature has mutated.