Valkyrie's Sword is a uncommon Artifact — Equipment card from Foundations Jumpstart (J25), collector number 276. Current market price: $0.28, TCGplayer market prices via Scryfall.
When this Equipment enters, you may pay {4}{W}. If you do, create a 4/4 white Angel Warrior creature token with flying and vigilance, then attach this Equipment to it. Equipped creature gets +2/+1. Equip {3}