 What if, out there in the filmy blackness of the void, there existed a threat so cyclopian in its immensity that even its nature could not be fully understood? I do not refer to the existential threat from the warp, no, but the entirely mundane threat of the Xenos. Since the first contact wars of eons passed, humanity has been assured time and time again that the alien exists only to be purged, its stain to be wiped clean from our human galaxy. For they do not, except mean us ill. We have millennia of experience in the pain that the Xenos have meted out upon our race. Because of their kind pollute this galaxy, the Aeldari, the green skins, the necrons, the towel, the hurud, the rackgall, the knib, the demi-urg, the knikassar, their hideous names fill archives, alongside copious evidence of their corruption and perfidy. These and many more are the Xenos we are aware of, whose obscenity is known, documented, and insofar as something so atrocious can be understood. Yet as I am sure the most keen of one's acolytes may be aware of, there is a gap in our knowledge here, and a rather monolithic one at that. Time and time again in one's studies of the great crusade has a name arisen, only to never be elaborated upon, clarified or expanded. Despite the clear and present danger it posed to not just the expeditionary fleets of the crusade as a whole, but possibly even the entire imperial endeavour. There is clearly more afoot here than I can yet comprehend, but it would be remiss of me as a scholar and historator to not address all that we may yet know, and if you will indulge me, I may posit some hypotheses of my own to fill the gaps in the archives. Though then, this is a record of one of the greatest threats the Imperium has ever faced, foe upon whose anvil a billion human lives were smote, and to whom we brought the calamity of Xenoside, the Rangda. What we know for certain about the Xenos species known as the Rangda is, to be perfectly frank, very little. What can be established is that they were a race of phenomenal power and capability, posing an existential level threat to the progress of the great crusade, subsequent to their first imperial contact, around the eight sixties of M-30. Upon the expeditionary fleets of the great crusade, first breaching the boundaries of what we now classify as Sygmentum Ultima in the Galactic East, the nascent Rangda were alerted to the military campaigns being waged by our glorious emperor, and moved to ensure they were stymied. To counter the threat, and with the aim of exterminating such a powerful foe, the Imperium waged at least three Xenosidal campaigns of such apocalyptic scale that it is widely considered to have been the greatest conflict in human galactic history until the Horus Heresy. Their expeditionary fleets were lost without a trace. Thousands of worlds were scoured of their very biospheres, rendering them uninhabitable husks. Billions of the Imperial Auxilia personnel, hundreds of Mechanicum Tagmata, dozens of Titan legions, and even hundreds of Legionneza startes were killed or destroyed in action. It was only through the direct intervention of the Emperor himself, and the combined might of at least three Astartes legions, that the very existence of the Imperium was insured, and the Rangda ultimately defeated. After almost a full century of conflict, the fate of the Great Crusade was once more assured, and the hegemony of mankind brought one step closer. Beyond this, a fairly perfunctory acknowledgement of the history of a major, and one would have expected, defining series of conflicts in Crusade history, the archives of the Rangda themselves are completely bare. While they appear again and again in the histories of Imperial military formations, nothing is recorded with any degree of precision about they themselves. We do not know if the threat they posed was biological, technological, psychic, or some hideous fusion of the three. We do not know the precise galactic volumes they once inhabited. We know nothing of their history, society, or culture. We do not even know what they looked like. Now, your humblest of servants will be the first to admit to the catastrophic failings of the Imperium when it comes to record keeping. That being said, the discrepancy here is… troubling. One finds it odd that when so many of the minor Xenocides of the Crusade were recorded in detail, and be it the Death Guard purging the Jokero, the Lunawals exterminating the Inter-X, the Blood Angels reaping bloody tolls from one ill-dory craft world after another, that the most fundamental alien threat to the nascent Imperium short of the green skins remains almost completely unrecorded. The first legion, Dark Angels, central in so many ways to the records concerning the Rangda, suffered more losses in those 70 or so years of campaigns than any of their brother legions did through the entirety of the Great Crusade itself. So much so that they were never, after that point, the most numerous of legions, forever losing their position to the 13th Legion Ultramarines. Why would such a sacrifice by the Angelus Tenebrus go essentially unrecorded? The very nature of their foes simply expunged entirely from Imperial records. One cannot attest to the loss of such knowledge. One has managed to gather all one can, drawn from dozens of different sources and Crusade Chronicles in order to do what one can't form as complete a picture as possible of the Xenos. I have heard that certain foundational records concerning the Dark Angels are in the process of being desequestered, thanks largely to a push from the Grandmaster of the Administratum, Violator Roscavlar, on behalf of the Lord Regent. Despite it must be said, strenuous pushback from the current Chapter Master. While one can but hope that they may contain precious information about the Rangda, I go to work with the tools I have, and so the work must continue. To address first the nature of this mysterious Xenos, we must turn to a series of references in relation to the history of various Astartes legions. Encounters have been mentioned between numerous Legiones Astartes forces and the Rangdan Ossiovores and Serbovores. When one parses out the root of these words, we are left with the implication that these were creations who consumed bones and brains, respectively, and are referred to as being specifically Rangdan. Where this thread becomes interesting is in the service record of the first Master of Ordnance of the 12th Legion Warhounds, later World Eaters, one Julljak Null. Null, who held the dubious honor of being one of the first of his Legion, interred within a Contemptor pattern dreadnought, fell in combat to the Slokth Murder Minds at Rangda. Aside from the implication that there was an identical Rangdan homeworld, it is deeply fascinating and disturbing that the hideous Slokth were there at present. We Xenos are one of the foulest of their kind, carrion cravers who desire above else the flesh of dead sentient beings, relishing in particular the cranial matter, from which they seem to derive an almost euphoric pleasure in consuming. It has been postulated by the Ordo Xenos that it is even possible for this species to extract the memories of the deceased from the cadavers they consume, and in doing so apply this stolen knowledge to better prosecute their hunts, for the Slokth possess a terrifyingly advanced mastery of biomechanical technology and elemental physics that far exceeds human capabilities are understanding. They are capable of interfacing with their technology in a manner only exceeded by the Tyranids, for the Slokth, though known to be roughly humanoid in shape, appear as more of a colony of hundreds of crawling, shifting, worm-like creatures, and can apparently alter their size and shape to small degrees. These maggot men, or worms that walk, to apply colloquial terms, persist to this present era. That is an unfortunate truth, yes, but their existence in the age of the Crusade, and indeed where, offers vital clues to the nature of the Rangda. Firstly, one wonders if there is a connection between the nature of the Slokth as brain eaters, and the existence of specifically Rangdan Serbovores. Is it possible, then, that the Slokth were a slave or client species subservient to their overlords? Seemingly. But I believe their nature is more of an offshoot of the Rangdan, that perhaps if historical inaccuracies can be accounted for, the Serbovores and the Slokth are one and the same, one species in different forms. The existence of the Tyranids lend some credence to this. Those extragalactic horrors are less one species and more one life-form, expressed again and again in an infinite number of varieties. If Xenos evolution can render something as foul as that, well, it is no great stretch to imagine that the Rangdan genome expressed itself in multiple evolutionary paths, and that the Slokth of today are simply the last pitiful and wretched survivors of a most righteous xenocide. There is, however, one important note to this, and that is a passing reference drawn from the combat records of the 14th Legion Death Guard to an encounter known as the Magined Torque Transgression. Taking place during the second of the Rangdan Xenosides, a base mechanic bark broke the imperial cordon surrounding Rangdan's space, impacting ultimately at the planet of Magined. The Death Guard, pursuing the Xenos vessel, suffered horrendous casualties at the hands of the Macrobeast within, saved only through the intervention of the 6th Legion Spacewolves, whose role in the 2nd and 3rd Xenosides appears crucial. Now, if any of one's acolytes are confused as to what exactly transpired here, know that I am with you, as this is the sole reference to both the base mechanic and their Macrobeasts in Imperial history. We can infer that the base mechanic are a Xenos race, blockaded within Rangdan's space, and their barks were ships of presumably immense size. The Macrobeast is an altogether more interesting affair, as it appears, given the naming conventions, to have been some sort of monstrous, organic, technological, or perhaps both construct, activated by its base mechanic handlers, or in this case, the presence of the Ligiones Astartes. Given the connections we have previously established between the Slokht and the Rangda, as well as the confirmed existence of multiple Rangdan Xeniforms, it is highly possible that the base mechanic are yet another expression of the Rangdan Overspecies. Perhaps given the name, those responsible for the maintenance of the race's biotechnological mastery, it would certainly not be a stretch in credulity to believe that, given the apparently overwhelming might of these Xenos, that such a cast would exist to specifically craft and create their weapons, as the Macrobeast seems to be. Believe of them, Acolytes, as akin to the Earth cast amongst the hated Tao, only perhaps even more integral. If we know little about the nature and appearance of the species, we know even less about their military capabilities, save for the utter and total threat they represented. Not even the Greenskin Empire toppled at Ullinor is spoken of in terms of the Xenosides. The Night Houses of Orlak and Malanax reference the Xenosides in their now sequestered chronicles, stating only that the conflict cost them many of their sacred night suits, but did serve to distinguish them amongst the ranks of the Questorus Imperialis and Mechanicum. The legios Grafonicus, Volchurum, and Caedianos fought with distinction, but suffered the losses of many of their god-engines to macro-scale Xenos war beasts, with Caedianos in particular noted as emerging from their campaigns as a shadow of their former selves. The Xenos wrecked untold havoc upon the First Legion, within whose sealed records one desperately hopes to find yet more clues. From what we do know, the First Legion encountered Rangda ships whose technology could accurately spoof Imperial sensor profiles, allowing them to slip through Imperial lines and launch devastating surprise attacks upon Crusade forces. The Angels, and their Primark, were known to have actively raged at never being able to strike at the foe from a position of advantage, with Rangdan hard ships consistently ambushing their fleets, not to mention instilling severe paranoia amongst Astartes forces seeking to reinforce their combat elements with other Imperial vessels and regiments. Often, fleet contests between the Crusade and the disturbing Xenos ships, described as bloated, spined things trailing biomechanical tentacles, would cost Imperial elements two ships for every one Xenos brought down. The Angels themselves, the First Legion, numerous more than any other, suffered a loss of over 50,000 of their Astartes in the Third Xenocide alone, unprecedented against a single enemy, and leading to the, if certain histories are to be believed, emergence of the 20th Legion Astartes, the Alpha Legion. As with all matters concerning this Legion, the truth is impossible to ascertain, as their ultimate emergence from the shadows is recorded not only having taken place here, during the latter stages of the Third Xenocide, but anywhere within a discrepancy of approximately 30 years Imperial standard. Nevertheless, given what has been supposed about the Alpha Legion's role up to this point, as effectively Astartes' counterintelligence operatives, the escalation from their position in the shadows to full front-line Legion, speaks volumes as to the threat the rang deposed and the devastation they inflicted. It was, however, seemingly the Emperor himself that broke the back of this wicked race, and doing so by, according to one's evidence on the matter, breaking the labyrinth of night. Now, inexperienced initiates may question the location or nature of this place or structure. Some may even suppose that this was a fortress of the Xenos themselves, some vast warren or citadel or hive from whence their forces were arrayed. But no, far, far from it. For there is only one place in the galaxy that goes by this name, although it is much more commonly referred to by its proper high gothic, the Noctis Labyrinthus. This is none other than the region of Mars between the Valles Marineris and the Tharsis Upland, access to which is banned utterly under the most total writ of both the Senatorum Imperialis and the Holy Synod of the Adeptus Mechanicus, and around whom rumors almost too dark and terrible to comprehend swirl. The Labyrinthus is a maze-like series of deep and almost impossibly steep walled valleys, well-named for both its impenetrability and the sheer lack of sunlight it receives. Once bore priceless mining operations, until the downfall of the Martian planetary regime during the Age of Strife and the subsequent rise of the Mechanicum saw it poisoned beyond habitation, with scouring radiation storms and mendicant nanophages, rendering its local atmosphere lethal to both flesh and metal. This is a lie, a convenient and largely accepted one, designed to keep the common herds from straying too deep into the canyons to learn of its truest secret. The Noctis Labyrinthus is the resting place of the Dragon of Mars. One wishes one could be more precise, as such a statement warrants further study. But that is all I have to go on. This very sentence was passed to me upon a scrap of data-waiter by parties unknown some time ago, and I have pondered its meaning greatly. It was not until I saw a reference to the Emperor and his breaking of the Nightly Labyrinth did I draw the connection, and realise there may be more to this. What is this dragon? Is it a weapon akin to the Mechanicum Ordinatus engines deployed against the Rangda during the Second Xenocide? If so, why did the Mechanicum not wield it? The Treaty of Olympus placed strict laws upon the chain of command divide between Imperial and Mechanicum forces, and while the Emperor himself, as Omnisiah of the Machine God, could have technically levied whatever he so wished from Mars, there is only one instance of him doing so directly, with the founding of the Ordo Sinister in the aftermath of the Xenocides. No. No, I fear the truth is altogether stranger and more terrible. Prachanse... Prachanse named Dragon is literal. After all, per the ancient Greek myth of the hero Theseus Titles, hunting the foul Minotaurus of the Labyrinth, such mazes have allegorically and, maybe literally, being used to contain monsters beyond most horrid imagination. But the Emperor, in his wisdom, have broken a labyrinth and freed the abominable entity within. In a desperate ploy to halt an enemy, unlike anything the Imperium had ever encountered, such mysteries they maddened me. Oh, to have true answers for once. This dreadful supposition ill becomes me. But I must question, I must. We shall have to shelve that particular line of inquiry for now. Well, precisely how yet eludes us. The Emperor's intervention is noted in most histories as being the turning of the tide of these conflicts, the point from which the Xenos were finally placed upon the back foot and the process of righteous extermination could begin in earnest. The final chapter to this sparse chronicle here is an interesting one. It is noted that the task of full extermination fell to the first legion and the sixth, the angels and the wolves doing their best to apply their particular talents to enact a decade-long series of biopagrams in order to ensure the rang-dan threat was utterly purged. A biopagram is a very specific means of dealing with a very specific type of foe, one who needs to be purged on, essentially, a cellular level, lest they resurge. Their actions are taken to ensure the ultimate destruction of green-skinned spores, gene-stealer genetic infection vectors, and even macro-scale tyrannid occupations, lest their insidious biologies wreak havoc upon a world's biosphere. This would mean that the Imperium, having emerged from 70 years of conflict with this particular enemy, feared the rang-dan at a level far beyond their sheer military might, and deployed the full level of two of the most lethal Astartes legions in the galaxy in order to effect a complete biological extermination of every genetic level of the foe. Both the Dark Angels and the Space Wolves are known, in the darker of Crusade annals, to have been legions whose remit was often to accomplish tasks none others could. The Wolves often bore the subricade of the Emperor's Headsmen, his bloody executioners, and while this threat was made good upon enough times to have them fully live up to it, it often remained more of an implicit warning. Intimidation should it be needed, their name alone would often carry that weight. The Angels, however, would have burned the galaxy to cinders, had the Emperor bade them so. Of that, I'm quite sure. Their Dreadwing was noted to use weaponry prescribed beyond use of any branch of the Imperial military, let alone an Astartes legion. Given this evidence, their role and presence during both the conflict and its aftermath, and what we have discerned about the nature of the Xenos themselves, I am drawn to hypothesize the following. The Rangdan Xenos were, effectively, a bacteria or a virus, a cellular lifeform that could, should they wish it, form into colonies of Gestalt combines, to sculpt and wield their blasphemous biology into forms better suited to kill and devour and propagate. I doubt it is for naught that the Serbovores and Osiovores were named as they are. An unspeakably hostile Xenos race that, once alerted to humanity's existence as a stellar power, moved to invade and defile in a way nothing else ever had. They did not desire to conquer us, as the Eildari may, or simply desire the conflict for its own sake, as is the case with the hated greenskins. No, it is likely their motive was consumption, parasitic colony things fusing with their technology on a cellular level, consumed by a hunger that is more akin to purest evil than that even of the Tyranids, yet millennia from arriving in our galaxy. Their nature as a maggot-like or viral race would make their presence phenomenally difficult to contain by conventional means, and necessitate only the harshest of extermination procedures to ensure their stain was wiped from history. Perhaps that is why, out of all the conflicts in the Imperium's history, it is their destruction that is referred to by the term Xenoside. Perhaps the pain of their passing was simply too much at the time, and the annals of the Great Crusade would rather forget than record. Should any more information come extant, with the sealing of the origin chronicles of the First Legion, I shall naturally relate them with all haste. But until such a time, and hopefully with your minds not utterly polluted with dread imaginings, Ave Imperator, Gloria in Excelsis Terra. This video and this channel is made possible through the incredibly kind support of my Patreon subscribers. If you'd like to help support the channel, head on over to patreon.com forward slash Oculus imperia if you want to kick me a buck or two to help keep the lights running and the scripts flowing. You can keep up to date with channel news if you follow me on twitter, at buttstuff kaiju, nope not changing that name anytime soon, and new this month, if you'd like to support the channel with some merchandise my very first t-shirts are up for sale on teespring.com forward slash Oculus imperia. Join the channel on discord as well, a link to all of this will be in the description below.