Old Flitterfang is a uncommon Legendary Creature — Rat Faerie card from Wilds of Eldraine (WOE), collector number 316. Current market price: $0.40 (foil $0.42), TCGplayer market prices via Scryfall.
Flying At the beginning of each end step, if a creature died this turn, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.") {2}{B}, Sacrifice another creature or artifact: Old Flitterfang gets +2/+2 until end of turn.