The Wizards of Once: Book 1

Once there were Wizards, who were Magic, and Warriors, who were not. But Xar, son of the King of Wizards, can't cast a single spell. And Wish, daughter of the Warrior Queen, has a banned magical object of her own. When they collide in the wildwood, on the trail of a deadly witch, it's the start of a grand adventure that just might change the fabric of their worlds.