Concussive Bolt is a common Sorcery card from Mirrodin Besieged (MBS), collector number 60. Current market price: $0.17 (foil $0.20), TCGplayer market prices via Scryfall.
Concussive Bolt deals 4 damage to target player or planeswalker. Metalcraft — If you control three or more artifacts, creatures controlled by that player or by that planeswalker's controller can't block this turn.