Saw is a uncommon Artifact — Equipment card from Duskmourn: House of Horror (DSK), collector number 254. Current market price: $0.21 (foil $0.46), TCGplayer market prices via Scryfall.
Equipped creature gets +2/+0. Whenever equipped creature attacks, you may sacrifice a permanent other than that creature or this Equipment. If you do, draw a card. Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)