Volcanic Salvo is a rare Sorcery card from Secrets of Strixhaven Commander (SOC), collector number 259. Current market price: $0.24, TCGplayer market prices via Scryfall.
This spell costs {X} less to cast, where X is the total power of creatures you control. Volcanic Salvo deals 6 damage to each of up to two target creatures and/or planeswalkers.