Excavation Explosion is a common Sorcery card from The Brothers' War (BRO), collector number 132. Current market price: $0.20 (foil $0.11), TCGplayer market prices via Scryfall.
Excavation Explosion deals 3 damage to any target. Create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")