Blue Sun's Twilight is a rare Sorcery card from Phyrexia: All Will Be One Promos (PONE), collector number 43s. Current market price: — (foil $1.08), TCGplayer market prices via Scryfall.
Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.