Quicksilver Dragon is a rare Creature — Dragon card from Duel Decks Anthology: Jace vs. Chandra (JVC), collector number 19. Current market price: $0.35, TCGplayer market prices via Scryfall.
Flying {U}: If target spell has only one target and that target is this creature, change that spell's target to another creature. Morph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)