Primal Might is a rare Sorcery card from Core Set 2021 (M21), collector number 197. Current market price: $0.29 (foil $0.34), TCGplayer market prices via Scryfall.
Target creature you control gets +X/+X until end of turn. Then it fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)