I originally thought that it would be the Scythians because the dear looks like some Scythian gold symbol, but the Sarmatians seemed to have replaced the Scythians when the mod got released and I don't see why EB would change its mind on this issue.
As for it being the Xiongnu, I really don't see why they would put them in and take the Yuezhi considering the fact that the Xiongnu were supposed to have destroyed the Yuezhi and sent the rest fleeing into other territories.
The Xiongnu and Yuezhi have too strong a relationship as far as combat goes for it to really be the Xiongnu, it would sort of be like taking Batman out of Gotham city and putting the Joker in his place, it just wouldn't work, you need the both of them to make it interesting.
Also the Xiongnu had conflicts with China and you'd need to have China in there to effectivly tell their story.
I really have no Idea who they could be, I would like to think Scythians.
This is fairly exciting.
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