Couriers (The Dragoneer, #6)

After Trysten and her horde recover from their rescue mission, they investigate a warning from Exeris and find a new threat to the kingdom amassing on the eastern border. With Cadwaller's resources depleted, Trysten prepares herself and the horde for a fighting season that will extend beyond the first snow.

When Rodden returns to Aerona with a Western delegation and an invitation for Trysten to engage in talks with the queen of Oppelnot, it is a welcome relief. It looks like an end to the centuries-old conflict with the Western kingdom might be near. But when Trysten meets the Opplian queen at last, she finds that the price of peace might be too high.