Hero's Blade is a uncommon Artifact — Equipment card from Doctor Who (WHO), collector number 241. Current market price: $0.36 (foil $0.40), TCGplayer market prices via Scryfall.
Equipped creature gets +3/+2. Whenever a legendary creature you control enters, you may attach this Equipment to it. Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)