Doomskar is a rare Sorcery card from Kaldheim Promos (PKHM), collector number 9p. Current market price: $0.79 (foil $1.29), TCGplayer market prices via Scryfall.
Destroy all creatures. Foretell {1}{W}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)