Goddess of the Ice Realm — David Drake

Garric and Sharina, Cashel and Ilna, are young brother and sister pairs whose destiny is to reunite the kingdoms of the Isles into one empire for the first time in a millennium.

As Garric and his retinue reach the island city of Carcosa, his benign wizard Tenoctris perceives a powerful supernatural threat directed against them. Ilna and her beloved Chalcus are sent to investigate a magical menace to shipping on the northern seas. Cashel is translated into another world by evil magic, and Sharina to yet another. All of them face deadly dangers and overcome them before they are again united during the terrifying and dramatic climax.

An action-filled and complex plot, loaded with surprises and startling revelations, romance and sorcery, Goddess of the Ice Realm is first rate fantasy.