Liliana's Devotee is a uncommon Creature — Human Warlock card from The List (PLST), collector number M21-109. Current market price: $0.24, TCGplayer market prices via Scryfall.
Zombies you control get +1/+0. At the beginning of your end step, if a creature died this turn, you may pay {1}{B}. If you do, create a 2/2 black Zombie creature token.