Siege Dragon is a rare Creature — Dragon card from Magic 2015 (M15), collector number 162. Current market price: $0.32 (foil $0.52), TCGplayer market prices via Scryfall.
Flying When this creature enters, destroy all Walls your opponents control. Whenever this creature attacks, if defending player controls no Walls, it deals 2 damage to each creature without flying that player controls.