So come these two entries, possibly based on (in game) fact or fiction, found here in the Imperial Archives.
Between demons and the gods, the Spirit World
A marginalia by, Ferdinand Cho Sok, the Imperial Spiritual Advisor to Shan Rohan, Third of His Name, year 137, 11th Age of the Empire
While those who are right thinking in the Empire honor the Four Houses, each in their measure, and those who seek the end of the world sell their souls to the demons of the Pit, we know there are other traditions that mediate between the visible and invisible world. On the one hand are those fae powers of nature superintended by the High Druid. On the other, and the focus on my thoughts here, are the powers of the spirits, ancestors and primal powers left from the Chaos War.
These are the province of what the barbarian tribes call the Shaman or Witch Doctor or Medicine Man. The tradition that most survives is the Chaos Shaman. While Chaos has not always been the totem of every Shaman, almost every one that practices in this day has been seduced by its power. Long ago, before the age of the Wizard King, the great mountain empires were served by Shaman-Priests who mediated between the lands of spirits, gods and mortal beings and Chaos was but one power they mediated. Their days are long gone, however, and all but their Cities of the Dead have been swallowed by the earth and turned to dust.
So now, Chaos reigns supreme among the Shamans, especially those Orcs who have not fallen to demon worship, and the wild human and half-Orc barbarians who both threaten and guard the frontiers of the Empire. It is a fearsome power to serve and to wield, but it is fickle and tricksy. For Citizens of the Empire, there is little appeal and no balm for the spirit in such practices. While the Emperor would never countenance suppression of our barbarian auxiliaries' spiritual practices, I have obtained permission to seek to convert them to more acceptable Imperial practice. The cult of Thar has always had special appeal, and the mighty Storm Hammer Priests have shown well against the Chaos Shamans. I have a hope that we shall see these practices fall more and more into disuse, pushed in the end to some few miserable tribes or Orc on the margins, of no threat to the Empire.
(historical note (marginalia in another's hand)): Advisor Cho Sok succumbed to a strangely incurable disease in 138 of the 11th Age and never saw his plans for proselytizing the barbarian tribes come to fruition)
A Warning
Imperial Eye of the Third Rank, Manco Hsieh
Year 200, 12th Age of the Empire
[Note, this field report from the Imperial Information Service (the Eyes of the Emperor) was found misfiled in Imperial Grain records; the misfiling could be because the Empire was teetering on the brink under the weight of the Zombie Plague (often blamed on the Diabolist) and the Imperial Bureaucracy was disintegrating with the rest of the Empire at the End of the Age]
I have found conclusive proof that THEY exist. As all people know, when the First Emperor and his Allies threw down the Wizard King (may his name be cursed), chief among his supporters was the Elf Queen. In the twelve years after the ascension of the First Emperor, half the children born to both humans and elves were half-elves. Fewer people take account of the fact that the victory by the First was also due in part to the role of the Orc Lord. When the Wizard King was most hard pressed by the First and his Elvish and Dwarven allies, it was the chaotic forces of the Orc Lord that broke the resistance of the Wizard King's reserves and allowed the Allied Forces to route the unsupported Royal Army.
Then the First was able to maim the Wizard King and cast him down while the Allies secured the power structures of the Kingdom to lay the foundation of the Empire. The Orc Lord's hordes, on the other hand, were busy chaotically rampaging. The Allies were easily able to persuade the now surrendered Royal Army to turn its power on the forces of the Orc Lord and drive them from the realm, thus saving most of the Royal territory to be converted to the Imperial Heartland.
The Orc Lord, pushed to the margins, swore never to forgive or forget that his people received no reward for ending the reign of the Wizard King.
And, among the human barbarian and Orc tribes that honored the primal Chaos spirits, in the twelve years following the Orc Lord's expulsion, there were born a twisted parody of the celebratory Half-Elves. These were the Man-Orcs. I have seen them, I have learned to know them, they are real, and they are a threat to the security of the Empire.
They are not Half-Orcs. The sages of the Archmage say that Half-Orcs are a supernatural response to the existence of Orcs that strengthen the communities plagued by the evil scourge of those vile creatures (now chiefly the barbarians at the margin of the Empire). The Man-Orc is a different creature. This is a creature that looks human, and seems human, but is an Orc down to the black pit of his soul. An Orc can instantly recognize the Man-Orc, and acknowledges both their kinship and the superiority of the Man-Orc.
This tribe of "wolves" in sheep's clothing has been infiltrating the Empire for years. They infest the barbarian tribes. Many have fallen to the siren song of the demonic powers, but most stay true to the ways of the Orc Lord's chaos spirits. They are cannibals of the most obscene kind, and this (as well as the ease with which true Orcs (but NOT Half-Orcs) identify them, may be among their few weaknesses. They not only like, but they crave human flesh (Orc flesh too, but the hunger is strongest for that of humans). They delight in dining on any intelligent creature, but they seem to need to devour the meat of humanity.
For over Eleven Ages they have been spreading throughout the tribes, the towns, and the cities. It is possible that they live among us even unto the sacred Imperial Services. We must beware and seek them out, turn them out before the Orc Lord rises again. They are his secret weapon, the knife at our throats.
We must find them and ward ourselves.
We must.