Hour of Reckoning is a rare Sorcery card from Ravnica: City of Guilds (RAV), collector number 21. Current market price: $0.58 (foil $9.85), 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.) Destroy all nontoken creatures.