Sarkhan, Dragon Ascendant is a rare Legendary Creature — Human Druid card from Tarkir: Dragonstorm (TDM), collector number 302. Current market price: $0.82 (foil $0.94), TCGplayer market prices via Scryfall.
When Sarkhan enters, you may behold a Dragon. If you do, create a Treasure token. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.) Whenever a Dragon you control enters, put a +1/+1 counter on Sarkhan. Until end of turn, Sarkhan becomes a Dragon in addition to his other types and gains flying.