An Autumn War: Long Price Quartet Series, Book 3

Otah Machi, ruler of the city of Machi, has tried for years to prepare his people for a future in which the magical andat, entities that support their commerce and intimidate all foes, can no longer be safely harnessed. But his efforts are too little, too late. The Galts, an expansionist empire from across the sea, have tired of games of political espionage and low-stakes sabotage. Their general, a ruthless veteran, has found a way to do what was thought impossible: neutralize the andat. As the Galtic army advances, the Poets who control the andat wage their own battle to save their loved ones and their nation. Failure seems inevitable, but success would end the Galtic threat.