"The Book of Atrix Wolfe" by Patricia A. McKillip. "Twenty years ago, the powerful mage Atrix Wolfe unleashed an uncontrollable force that killed his beloved king. Now, the Queen of the Wood has offered him one last chance for redemption. She asks him to find her daughter, who vanished into the human world during the massacre he caused. No one has seen the princess-but deep in the kitchens of the Castle of Pelucir, there is a scullery maid who appeared out of nowhere one night long ago."