Days of Air and Darkness — Katharine Kerr

The city of Cengarn is under siege. Armies both astral and physical are massing for and against the goddess Alshandra, who seeks to 1 prevent the birth of one fate-hound child. It falls to the dweomermaster Jill and her allies to protect the child's human mother, Princess Carra--and Deverry's already foretold future--by magic and by might. But as the warrior Rhodry wings toward the battle on dragonback, he cannot know that soon he will face his ancient enemy, Alshandra's high priestess Raena, who will use any means to destroy him. Their confrontation could turn the tide of the siege--and change the fate of Deverry forever....