Grimgrin, Corpse-Born 
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.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL