Kellan, the Kid is a mythic Legendary Creature — Human Faerie Rogue card from Outlaws of Thunder Junction (OTJ), collector number 213. Current market price: $4.21 (foil $3.58), TCGplayer market prices via Scryfall.
Flying, lifelink Whenever you cast a spell from anywhere other than your hand, you may cast a permanent spell with equal or lesser mana value from your hand without paying its mana cost. If you don't, you may put a land card from your hand onto the battlefield.