Cut Your Losses is a rare Sorcery card from Streets of New Capenna Promos (PSNC), collector number 38p. Current market price: $1.79 (foil $1.91), TCGplayer market prices via Scryfall.
Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.) Target player mills half their library, rounded down.