Oni-Cult Anvil is a uncommon Artifact card from The Brothers' War Commander (BRC), collector number 127. Current market price: $0.26, TCGplayer market prices via Scryfall.
Whenever one or more artifacts you control leave the battlefield during your turn, create a 1/1 colorless Construct artifact creature token. This ability triggers only once each turn. {T}, Sacrifice an artifact: This artifact deals 1 damage to each opponent. You gain 1 life.