Ratchet Bomb is a rare Artifact card from Scars of Mirrodin (SOM), collector number 196. Current market price: $0.43 (foil $2.88), TCGplayer market prices via Scryfall.
{T}: Put a charge counter on this artifact. {T}, Sacrifice this artifact: Destroy each nonland permanent with mana value equal to the number of charge counters on this artifact.