Proof of Patience (book 11)

Emperor Jorqel is determined to keep Kastanian momentum going, despite the rising number of enemies facing the recovering empire.  In the west, his step-brother Prince Argan takes the initiative against the Epatamians, dragging a less enthusiastic Prince Amsel into the conflict.  Argan’s and Amsel’s relationship is further strained through Jorqel’s reorganisation of their respective responsibilities and Argan feels disadvantaged, so he decides to create a new title for himself against the wishes of the emperor.

Jorqel’s youngest daughter Zora is also proving troublesome; her criticisms of her older sister Merza results in a falling out between the siblings and Zora’s unwise comments to her father
on certain imperial policies earns her being exiled from the capital. 

All the while in the background the rival House of Kanzet is developing a scheme to ruin the reputation of the Koros, using corrupt merchants and companies to try to bring about their
downfall and to take over the empire for their own financial benefit.  It is left to Zora to find the heart of the plot and to deal with it.