Fated Clash is a rare Sorcery card from Final Fantasy Commander (FIC), collector number 449. Current market price: $7.94 (foil $6.79), TCGplayer market prices via Scryfall.
You may cast this spell as though it had flash if a creature is attacking and a creature is blocking. Target creature you control and target creature an opponent controls each gain indestructible until end of turn. Then destroy all creatures.