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In the Survivors' Future, the Farchitects protect and preserve the last, dying city, Alluvium, last bastion of humanity. Theirs is a collective, harsh existence. Genetic predetermination decides their fate. All sacrifice for the city. There is no love, no hate, and no desire. There is only unity of purpose and, finally, death. But one fateful night, one of their number discovers a mysterious device, a device that transports her far from her home, a device that takes her to a distant, wind-swept plain. There she encounters a strange people whose leader has been stricken by a mysterious illness. Trapped, she must find her way home, but to do so she must arm herself with knowledge that her dying future has long forgotten. She must restore this leader to his rightful path, for he is to be none other than the Great Khan, Genghis.
History has been diverted from its proper path and only she can set it right.

https://www.amazon.com/dp/B00T39DKIS