Firemantle Mage is a uncommon Creature — Human Shaman Ally card from Battle for Zendikar (BFZ), collector number 145. Current market price: $0.13 (foil $0.39), TCGplayer market prices via Scryfall.
Rally — Whenever this creature or another Ally you control enters, creatures you control gain menace until end of turn. (A creature with menace can't be blocked except by two or more creatures.)