The Sound of Starfall (The Last Ballad, #1.5)

This is the end

The Warlocks of Yehven have ruled over the Remembered Lands with their songs of dark sorcery since the skies were new.
But now, beneath the shadow of an approaching comet, a mysterious death cult from the wild lands have arrived in the name of Nature to exterminate the Warlocks and their sorcerous Words with them.
As the death cult breaches the walls of the Golden City and Ailar crumbles into anarchy, a Warlock, an enslaved man, and a guard are forced to make decisions that will shape the world for thousands of years to come.

The sky is falling
Nightmares are waking
The sound of starfall eats all else