The Reaver Cleaver is a rare Legendary Artifact — Equipment card from Dominaria United Commander (DMC), collector number 8. Current market price: $28.78, TCGplayer market prices via Scryfall.
Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens." Equip {3}