Festerleech is a uncommon Creature — Zombie Leech card from Murders at Karlov Manor (MKM), collector number 85. Current market price: $0.17 (foil $0.23), TCGplayer market prices via Scryfall.
Whenever this creature deals combat damage to a player, you mill two cards. {1}{B}: This creature gets +2/+2 until end of turn. Activate only once each turn.