As Foretold [Amonkhet Promos]

Set: Amonkhet Promos Type: Enchantment Mythic Cost: {2}{U} At the beginning of your upkeep, put a time counter on As Foretold. Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with converted mana cost X or less, where X is the number of time counters on As Foretold.