From about 1360-1460, the nomads of Sheng Seleris terrorized the areas adjacent to Pent – Kralorela, Ignorance, Prax, Teshnos, and Peloria. The Celestial Empire was focused on Sheng Seleris and his Enforcers, an elite band that rode atop whatever hierarchy of people they ruled. Large roving bands of nomadic horsemen devoted to Sheng Seleris’ will turned fields into grasslands and terrorized the local population.
These nomads were not administrators – that work was given to subordinate officials of Pelorian, Kralorelan, or Teshnite origin. People from one region would be sent to administer another region – so Kralorelans scribes might be sent to Peloria, Pelorian scribes to Teshnos, and Teshnite scribes to Kralorela, and so on. Government was simple – worship Sheng Seleris and his Bursts, pay the demanded tributes, ritual obeisance to the representatives of Sheng Seleris, and ABSOLUTE OBEDIENCE to his representatives. Beyond that the subject peoples were largely left to their own. Rebels were dealt with brutally and with extreme terror – collective punishment was the norm.
The army of Sheng Seleris was large, fast moving and possessed incredible magical power. A few beings (ok, Godunya himself) were powerful enough to tangle with Sheng Seleris, but the norm was whoever opposed Sheng Seleris directly was screwed. He was powerful enough to invade the Red Moon and scar it. Sheng Seleris respected some Nysalorean schools, and also his techniques bore some superficial similarities to aspects of Kralorelan mysticism (particularly the relationship between the Dragon King and the Exarchs, which was echoed with Sheng Seleris and his Bursts).
After 1460, his empire quickly collapsed. Without Sheng Seleris, the nomad bands retreated to the Redlands. Hon-eel had many contests with them, defeating the Reverend Horse Mother in the contests over Yelm. In 1503 the Opili Nation unified many Pentan tribes and invaded Oraya, leading to the terrible Night of Horrors in 1506, which destroyed both the Lunar Army and the Pentan nations.
I tend to associate Sheng Seleris with the Tibetan Buddhism story of Rudra. Quoting the Wikipedia version of the story:
Rudra is a demon, formerly a human monk of noble origin named Koukuntri and then Tharpa Nakpo, who misunderstands dharma and engages in a life of vice and is condemned to Naraka. After 20.000 impure lives, he is eventually reborn as a demon in Sri Lanka by a prostitute who sleeps with three kinds of supernatural creatures, giving him three heads. His birth brings about plague and famine, so he is banished to a charnel ground, but he survives by devouring his mother’s corpse and returns in order to conquer the world. Becoming the lover of the rakshasha queen Krodhishvari, he battles the gods, who are terrified of his extraordinary power and call the Buddhas and boddhisattvas for help.
We can call that a failed mystic – as Sheng Seleris accumulated vast magical power through terrible austerities that used to conquer the world. Kralori mystics would say he COMPLETELY MISSED THE POINT (and thus he is a failed mystic), but he did nearly conquer the world! Sheng Sellers’ successes of course influenced later Lunar magical techniques – as how could they not?