The Mirror Empire: Worldbreaker Saga 1

On the eve of a recurring catastrophic event known to extinguish nations and reshape continents, a troubled orphan evades death and slavery to uncover her own bloody past. As the dark star of the cataclysm rises, an illegitimate ruler is tasked with holding together a country fractured by civil war, a precocious young fighter is asked to betray his family and a half-Dhai general must choose between the eradication of her father's people or loyalty to her alien Empress.