Lethal Throwdown is a uncommon Sorcery card from Modern Horizons 3 (MH3), collector number 99. Current market price: $0.20 (foil $0.26), TCGplayer market prices via Scryfall.
As an additional cost to cast this spell, sacrifice a creature or sacrifice a modified creature. (Equipment, Auras you control, and counters are modifications.) Destroy target creature or planeswalker. If the modified creature was sacrificed, draw a card.