Thundermaw Hellkite is a mythic Creature — Dragon card from Iconic Masters (IMA), collector number 149. Current market price: $2.66 (foil $8.56), TCGplayer market prices via Scryfall.
Flying Haste (This creature can attack and {T} as soon as it comes under your control.) When this creature enters, it deals 1 damage to each creature with flying your opponents control. Tap those creatures.