Reconquêtes Series by Sylvain Runberg

This opening episode begins with the Hittites' bloody Urar conquest, which is the first stage of a fierce conflict. Urar belongs to the rulers Marak, Kymris and Simmissee, three ancient rivals who have now united and formed one fearsome fighting force whose sole preoccupation is killing. Woe betide anyone who provokes their wrath!

The Horde of the Living continues its relentless advance, growing increasingly certain of its invincibility. However, the alliance of the three kings is more fragile than they seem to think it is. The Hittites seems to be mastering their weaponry in a whole new way, and cracks are starting to appear in the Horde's unified facade. Will Thusia continue to observe from the sidelines, or will she have a greater part to play...?

The Horde, that reunites the three largest realms of Pre-Antiquity, continues its unstoppable advance. But it's becoming increasingly clear that its greatest enemy is perhaps its own unique founding concept. While the brawls between the three clans begin to tear the great army apart, there is also a storm brewing in Thusia's mind, as she is forced to choose sides.

The Horde of the Living is growing ever weaker in consequence of the constant attacks from the Hittites. Their only hope is to sneak into enemy territory and kill the Hittite king. Which is how Thusia ends up mounting Marak's griffin and setting off for the Hittite capital. If she succeeds, the Horde will survive.