Firbolg Flutist is a rare Creature — Giant Bard card from Battle for Baldur's Gate Promos (PCLB), collector number 174s. Current market price: — (foil $0.88), TCGplayer market prices via Scryfall.
Enthralling Performance — When this creature enters, gain control of target creature you don't control until end of turn. Untap it. It gains haste and myriad until end of turn. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)