Greg Keyes 
The Wind that Sweeps the Stars 

A taut high fantasy as an assassin must destroy an empire from within, eliminating wizards, their demons, and even the emperor. For the lives—for the very souls—of her people, she must succeed within a single day, or her homeland will be destroyed.
ALONE AGAINST AN EMPIRE.
When Yash of Zeltah arrives in the fortress city of Honaq she is greeted as a barbarian, a simple pawn. Her marriage to prince Chej has been arranged, they say, to avert war. Yet she knows the truth, for the armies already ravage the land. A skilled and deadly assassin, there is more to Yash than any might suspect. Before another day can pass, she must defeat the masters of the nine towers—the plagues, magics, and monsters they control, the soldiers they command. Without raising an alarm, she must kill all who oppose her—even the immortal emperor. The lives and souls of Zeltah, the people and the land upon which they live, all depend on it.

About the author

Born in Meridian, Mississippi, Greg Keyes has published more than thirty books, including The Basilisk Throne, The Age of Unreason, and The Kingdoms of Thorn and Bone, also writing books for Babylon 5, Star Wars, Planet of the Apes, The Avengers, and Pacific Rim, and novelizing Interstellar and Godzilla: King of the Monsters. He lives, writes, fences and cooks in Savannah, Georgia. He is found on Facebook at https://www.facebook.com/greg.keyes1.