Hellkite Charger is a rare Creature — Dragon card from Commander Masters (CMM), collector number 232. Current market price: $3.47 (foil $6.40), TCGplayer market prices via Scryfall.
Flying, haste Whenever this creature attacks, you may pay {5}{R}{R}. If you do, untap all attacking creatures and after this phase, there is an additional combat phase.