Winternight Stories is a rare Sorcery card from Tarkir: Dragonstorm Promos (PTDM), collector number 67s. Current market price: — (foil $3.75), TCGplayer market prices via Scryfall.
Draw three cards. Then discard two cards unless you discard a creature card. Harmonize {4}{U} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)