Karrthus, Tyrant of Jund is a mythic Legendary Creature — Dragon card from Alara Reborn (ARB), collector number 117. Current market price: $6.18 (foil $17.08), TCGplayer market prices via Scryfall.
Flying, haste When Karrthus enters, gain control of all Dragons, then untap all Dragons. Other Dragon creatures you control have haste.