Rosethorn Halberd is a common Artifact — Equipment card from Throne of Eldraine (ELD), collector number 175. Current market price: $0.08 (foil $0.24), TCGplayer market prices via Scryfall.
When this Equipment enters, attach it to target non-Human creature you control. Equipped creature gets +2/+1. Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)