This competent general is called Jean. He debuted as a Major of Kioka Republic in volume 3, and would one day be known as "The Unsleeping Radiant General", alongside Ikta, who would be known as the "Frequently Slacking, Frequently Victorious Resourceful General" (it just doesn't translate into English well).

Ikta and Jean had the first major square off in volume 3. He was on the ground commanding his forces and did have a continuous presence in this volume. In fact, he gave Ikta a hard time and nearly outmaneuvered him. Ikta triumphed only because he was willing to throw away his pride.

His presence was much less until volume 5 and 6. Because:
first half of volume 4 - Ikta and gang needed to see to a corruption issue in a particular town
2nd half of volume 4 till 1st half of volume 5 - naval battle with Kioka, so the focus on the enemy side is more on the naval commander, who has a talent in reading winds and currents thanks to her bird. In the Empire side, more focus is given to the Yurugus family who originated from a famed family of explorers, and is now one of the 3 great families alongside Igsems (Yatori) and Remions (Torway).

Jean reappeared in volume 5 and 6 and was holding a mine that the Empire was laying siege. There wasn't much of a square off because the Empire needed to retreat to deal with a civil war. Ikta formed a 3rd faction by raising his father's flag.

There is also another antagonist, a cunning fox, and that is the prime minister of the Empire.

Now the civil war is over, and Chamille is consolidating her position, strengthening her borders against Kioka, and also dealing with espionage.

I haven't read the latest volume yet, but Jean did appear in the last volume showing some aspects of Kioka. So this is where we are at.