High Priestess — Brian K. Stoner

The Daemons race that threatened the world for so long is finally gone. The Seriani are three, and relative peace reigns across the land. Twelve-year-old Leliah, already called the Dragon Mage, has grown up in a world without threat, without a single enemy of consequence. Unbeknowst to all, however, a small piece of the Black Void escaped the Daemons' destruction, and has grown in the shadows, giving rise to an evil the likes of which the world has never seen. With her mother beyond reach, Leliah becomes the unwitting focus of the creature's thirst for revenge.