Arc Spitter is a uncommon Artifact — Equipment card from Streets of New Capenna (SNC), collector number 233. Current market price: $0.25 (foil $0.30), TCGplayer market prices via Scryfall.
Equipped creature has "{1}: This creature deals 1 damage to target creature that's blocking it." Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)