Winnowing is a mythic Sorcery card from Lorwyn Eclipsed (ECL), collector number 382. Current market price: — (foil $8.92), TCGplayer market prices via Scryfall.
Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) For each player, you choose a creature that player controls. Then each player sacrifices all other creatures they control that don't share a creature type with the chosen creature they control.