Argrath seems like a bit of a mix of various Nomadic "Hero's" such a Ghinggis Khan who was also a slave for and was also famous for his fertility (think they say 1 in 7 Asians have his DNA). Timur i Lenk who had all the stars linked up at his birth to give good omans and great Propaganda. Attalia "The Wrath of God" and various others who all basically used a mix of terror and great cavalry tactics to build an Empire from feuding steppe Clans. While at the same time removing a lot of annoying civilized settlements which were clutting up good pasture land in the process. Like the Settlements in the river of Cradles destroyed by Argrath and his horde who players of Borderlands spent so much time and effort to build !! Thanks Argrath !!!
Big moment of danger for all of these Nomadic Empires based a "Chasismatic" founder who has lots on sons by different wives is when that founder dies. Attalia is believed to have choked on a nose bleed or his own vomit at his latest wedding feast and his "Empire" fail to bits as various sons fought and former "allies" revolted. This is a pretty common end for Nomadic Empires. The Timurids also went down hill rapidly after the death of Timur though later generations were able to establish a new Empire in India.
The Mongols are pretty unique in being able to keep expanding for several generations after the death of Ghinggis though the Empire did start to split up into various factions like the Golden Horde, Ilkhanids, Yuan dynasty in China etc fairly quickly after the death of Ghinggis.
Argrath's Empire with no obvious heir and made up of an alliance of stuffy old traditional Nomadic Waha Khans, Olanthi farmers and various Pirates and Storm Bull Fanatics who are great in a fight but probably dire at local admin and actually getting anything to work would seem to have nothing at all holding it united apart from Argrath. Which rather leaves the question of how many bits does it break up into and does anyone try to re-unite them (bit like Alaxanders generals did after his death).
With succession fights, Nomads v Farmers, Pirates going back to traditional trade
and all of the other tribal and clan feuds do the Seven Mothers and Lunar Int services actually have to do much with the oil and matches before Argrath and his Empire goes up in flames?