The Winter King : Silver Mage Series — P.L. Nunn

With the allied forces of the south turned against them by the mysterious and powerful Prophet, the Dante Epherian and his arcane allies take refuge in the wintry kingdom of Sta-Veron, the seat of the Kastel's power. But having lost his chance at subsuming Dante's power, the Prophet turns his focus on destroying Dante's circle of friends and taking as his new host, the Winter King himself. Unless Dante can prevent the Prophet from adding Kastel's considerable power to his own, the world is doomed. Book 2 of the Silver Mage Series.