Rimuru, Demon Lord

Eminence:: Whenever a creature an opponent controls die due to combat damage, exile it with a predator counter.

Flying Menace

Creatures you control get +1/+1 for each creature exiled with a predator counter.
Rimuru has the activated abilities of creatures exiled with predator counters
{x},{t}: Put a creature exiled with a predator counter onto the battlefield under your control where X is that creatures mana value. If That creature would die, exile it facedown instead