Rennala, Full-Moon Queen

Each sorcery card in your hand pays for {1} of this card's mana cost.
Once per turn, you may reveal the top card of your library. If that card is a sorcery card, you may cast it for half of its converted mana cost, rounded down.
When Rennala, Full-Moon Queen is on the battlefield, sorcery cards that have been exiled may be played from exile.