Singing Towers of Darillium

Each nonland card in your hand without foretell has foretell. Its foretell cost is equal to its mana cost reduced by 2. (During your turn, you may pay 2 and exile it from your hand face down. Cast it on a later turn for its foretell cost.) Whenever chaos ensues, you may cast a foretold card you own from exile without paying its mana cost this turn.