Forebear's Blade is a rare Artifact — Equipment card from Dominaria Promos (PDOM), collector number 214p. Current market price: $1.03 (foil $2.50), TCGplayer market prices via Scryfall.
Equipped creature gets +3/+0 and has vigilance and trample. Whenever equipped creature dies, attach this Equipment to target creature you control. Equip {3}