Frostborn
The Gray Knight

Ridmark Arban was once a Swordbearer, a knight of renown. Now he is a branded outcast, stripped of his sword, and despised as a traitor. But he alone sees the danger to come. Calliande awakens in the darkness, her memories gone, and creatures of terrible power hunting her. For she alone holds the secret that can save the world . . . or destroy it utterly. The secret of the Frostborn.