Quag Feast is a rare Sorcery card from Aetherdrift Promos (PDFT), collector number 100s. Current market price: — (foil $0.38), TCGplayer market prices via Scryfall.
Choose target creature, planeswalker, or Vehicle. Mill two cards, then destroy the chosen permanent if its mana value is less than or equal to the number of cards in your graveyard.