Uncover the Moon-Letters is a rare Enchantment card from The Hobbit (HOB), collector number 57. Current market price: $0.26 (foil $0.33), TCGplayer market prices via Scryfall.
Whenever you cast a noncreature spell, you may draw X cards, where X is the amount of mana spent to cast that spell. If you do, discard two cards.