Thraximundar 
Legendary Creature — Zombie Assassin
Haste Whenever Thraximundar attacks, defending player sacrifices a creature of their choice. Whenever a player sacrifices a creature, you may put a +1/+1 counter on Thraximundar.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL