Ancestral Blade is a common Artifact — Equipment card from Double Masters (2XM), collector number 3. Current market price: $0.12 (foil $0.20), TCGplayer market prices via Scryfall.
When this Equipment enters, create a 1/1 white Soldier creature token, then attach this Equipment to it. Equipped creature gets +1/+1. Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)