The Burning Sky by Sherry Thomas

It all began with a ruined elixir and a bolt of lightning. Iolanthe Seabourne is the greatest elemental mage of her generation—or so she’s been told. The one prophesied for years to be the savior of The Realm. It is her duty and destiny to face and defeat the Bane, the most powerful tyrant and mage the world has ever known. This would be a suicide task for anyone, let alone a reluctant sixteen-year-old girl with no training. Guided by his mother’s visions, committed to avenging his family, Prince Titus ha