Grimgrin, Corpse-Born{3}{U}{B}

Legendary Creature — Zombie Warrior

Grimgrin enters tapped and doesn't untap during your untap step. Sacrifice another creature: Untap Grimgrin and put a +1/+1 counter on it. Whenever Grimgrin attacks, destroy target creature defending player controls, then put a +1/+1 counter on Grimgrin.