2011’s Harbinger of the Storm is the second volume in Aliette de Bodard’s Obsidian and Blood Trilogy.
Acatl, Tenochtitlan’s High Priest of the Dead, knows immediately when the Revered Speaker Axayacatl, Emperor of the Mexica, dies. The Emperor was vital to the maintenance of the wards that protect his empire from star demons, and his death has weakened the wards. A new emperor must be installed … quickly!
The new emperor will be chosen by the council, but the council finds itself under attack. A star demon has invaded the imperial palace and dismembered one of the councillors. Since the wards are only weakened, not gone, the star demon could not have entered without inside help. Some human sorcerer is meddling. It is up to Acatl to discover the identity and motives of the culprit, then frustrate the plot.