All three books in the Europa trilogy of dark fantasy adventures:
Book 1 - Omar the Immortal
In the dazzling and dangerous land of Marrakesh, globe-trotting scholar Omar Bakhoum joins an airship expedition into the freezing north in search of a fabled country called Ysland, but howling ice storms, legions of ghosts, and a deadly samurai stand in his path.
His journey has barely begun before the members of the expedition team begin dying of a strange and sudden disease, and as the last remaining foreigner on board, Omar is accused of these murders. The one thing that can help him find the real killer is Omar's ancient sword, haunted by the souls of thousands of dead sages and warriors. But this sword may be the very thing that dooms the entire expedition to a watery grave.
Book 2 - Freya the Huntress
In the snowy highlands of Ysland, Freya's sister is attacked by a diseased creature. Now, Freya has only a few hours to find a cure before her sister becomes a monstrous fox demon.
With her husband Erik and the young witch Wren, Freya explores deserted cities full of ghosts, meets lonely survivors on the edge of madness, and finally seeks answers in Rekavik where she meets the witch queen Skadi and her cruel warrior Leif Blackmane. Freya learns that the only person who can cure the demon plague is a certain traveler from a distant land, but he was murdered five years ago...
Viking warriors and ravening demons threaten her on all sides, but not even death itself will stop Freya from saving the people she loves.
Book 3 - Wren the Fox Witch
The young witch Wren follows her mentor Omar across the frozen wastes of Europa to the warring cities of Constantia and Stamballa, where war is the least of her problems.
While Omar leads a desperate battle against an undead army, Wren must face the immortal witch Baba Yaga, who has gone mad grieving for her son, Koschei the Deathless. During their duel, Wren confronts the spiteful souls of her dead teachers, her own secret fears made flesh, and the waking nightmares of Baba Yaga herself.
But Omar has taught her how to control the aether mists that reveal the souls of the dead, so if Wren can somehow defeat the mad crone, she may gain the power to end the entire war by herself.