 The reasons why the multiferous Xenos races of our galaxy desire humanity's extermination are as diverse and pathetic as they are themselves. For the Eldari, they fear that our species has done what they could not, rule the galaxy with an ironclad manifest destiny none can deny. Their Drukhari kin simply wish to use us as a sport, or to prolong their disgusting existences yet a few more solar days. The upstart Tau seek to carve their own stellar empire, ideologically driven to oppose all that our great Imperium stands for. In a similar fashion, albeit separated by the gulf of millions of years, the hosts of the necrons rise from their sepulchral complexes to reclaim a galaxy they foolishly believe is still theirs by ancient right. Even the green-skinned menace desires to destroy us if only for the thrill and nourishment of combat their base barbarian desires driving them to war for its own sake. But there is another scourge that we yet face, one whose driving force would be considered pure were it not for the sheer hideousness of its design. Hunger, dear Acolyte, hunger simple yes, but of a ravenous scope and scale that the human mind would shatter in an attempt to truly perceive it. This species is driven by an appetite so blasphemously ravenous they have stripped uncounted worlds nay even uncounted galaxies of every molecule of organic matter. They are a plague of old terror on an impossible cyclopean scale, a scourge from the void that has no ideology, no desires, no fears, no wants or needs beyond its horrific drive to consume. It possesses no name beyond the one we have given it, for it has no need of one. It cannot be bargained with, it does not hold the concepts of surrender or mercy or parlay as anything other than abstract nonsense. Against this foe there is no option but to visit upon them the Emperor's most total and complete extermination for their progress must be arrested lest they inflict upon our galaxy what they have perhaps done to others for eons uncounted. Know then that this is a record of the scourge from the great darkness, the pangalactic infestation, the hive fleets of the great devourer, the tyrannids. The tyrannids are a composite species, one race forming what would be considered to xenobiologists an entire biosphere. Despite the multiple and incredibly diverse range of tyrannid xenophorms they are all united through a single shared biology and, in this way, effectively function as a single organism, albeit on a scale quite literally incomprehensible by lesser minds. This macro-organism has, apparently, one goal, the consumption of organic matter to produce yet more of itself, to on the fact, reproduction, but a game on a scale incomprehensible. Every facet of their biology is engineered by the species itself to expressly achieve this goal, for the tyrannid race has total control over its own biological makeup, able to alter whatever subgenus is necessary to meet any challenge or overcome any prey. They construct their technology not out of metal but out of flesh, everything from simple tools to the void-faring ships of the race themselves rendered from tyrannid DNA, sculpted with horrific purpose. From the bullet creatures, in a termigant bioweapon to the brood creatures that disgorge bioforms into a planetary atmosphere, all are an extension of the same species. A sheer range of organic structures, systems, and physical features would usually demand re-classification into separate genuses, but, even more so than the green-skinned species, each creature of this race is unquestionably tyrannid. The race does not, however, run on simple primal instinct alone, no. By dread intelligence are the swarm fleets controlled and directed. The mere existence of untold billions of creatures merges in the realm of Sikana. To create a blasphemous gestalt intelligence, imperial records have come to term the Hive Mind. As with all things concerning this predator species, this is not the name it has given itself, for this macro-mind has no need of such paltry things. The collective consciousness drives and empowers every tyrannid creature, from the smallest to the largest, directing Hive fleets as a human would direct limbs of their body. This does not mean, however, that every creature in the swarm is itself a Sikur. The lesser entities of the race are little more than beasts, bred with rudimentary, but nonetheless incredibly vicious predatory instinct. When the Hive descends upon a prey world, larger creatures serve as psychic conduits, synapse nodes, through which the will of the Hive Mind can direct the swarm. During battle it is common now that the larger bioforms be given higher target priority, as disrupting their control over the herds of lesser beasts leaves the latter loose from Hive control, and prone to cannibalism and wanton violence. The Hive Mind itself is impossible in both scale and scope. Human Sikurs, who have attempted to contact it in a vain attempt to discern motive or intent from its depths, have found their minds simply shattered into a billion pieces by their efforts, even to the point of simply being killed outright. Only a single Sikur has managed to attain this feat. Tigris, chief librarian of the Ultramarine's chapter of the Abdetus Astartis, somehow retaining his sanity in the face of the hideous intelligence. Through it appears sheer force of will. He has been, however, but one amongst thousands. The Hive Mind is powerful enough and broad enough to create a shadowing effect in the volume containing a Tyrion Hive fleet, blotting out astropathic communication in the warp entirely and disrupting the minds of Sikurs in closer proximity, visiting upon them feelings of immense terror and crushing horror. In a manner akin to a localized warp storm, even the light of the Emperor, the Astronomican upon Holy Terra itself, is occluded. The prey world selected for consumption by this Hive fleet is thus utterly cut off from the rest of the galaxy, helpless in the face of the encroaching predator swarm from the outer dark. It is this consumption on planetary scales, nay a galactic scale, that drives the Hive Mind. Tyrionid creatures on every level are engineered to be apex predators, driven to simply annihilate all before them until not remains but the biomass, the nutrient soup of a planetary volume. Once all resistance has been utterly scoured, yet more specialized creatures are unleashed to strip every molecule of organic matter from the planet's surface, leaving behind a blasted arid husk of an utterly dead world. Through their consumption, the race by means largely unknown, examines, divides and metabolizes genetic characteristics of the species it consumes, adding biological traits to its own biological makeup for future use. An apex synapse creature, dubbed a Norn Queen, after Captain Uriel Ventress of the Ultramanines Chapter encountered one in the orbit of Tarsus Ultra, is apparently responsible for the direction of this localized hyper-evolution, sifting the resources garnered from their planetary feasting and scrutinizing the collective memory of the conflict to better discern the bioforms required to continue it. In this way, attempting to fight a tyrionid swarm becomes an almost impossible task, as barely as one wave of beasts slaughtered, then the next is disgorged, hyper-adapted to better combat the weapons and tactics that were employed against their fallen brethren. It is not, by any accurate means, possible to discern from whence the tyrionids originated, for they are not native to our galactic volume. Indeed, it is not even possible to pin down even which galaxy they emerged from. All that imperial scholarship can be certain upon is that they have emerged from the deep intergalactic void space, from somewhere else within the local group galactic cluster. Quite how long their fleets of bioships crossed the void is itself also unknown, ranging anywhere from millennia to potentially millions of years. It has been theorized by those privy to this damnable knowledge that, given how the race functions, it is possible they have left tens, hundreds, even thousands of dead galaxies in their wake, and billions of extragalactic xenos dead and rendered into the nutritious chemicals that fuels the ever-expanding predator. We will likely never know. The hive mind is not an intelligence that can be spoken to, and the species itself not one with any care for records or history or knowledge. It simply is. It has always been. It itself likely does not know. Or indeed care. Blasphalies. Utter. Excuse me. Imperial histories officially note the date of first contact with the Tyranid race as being 745 M41, upon the planet Tyran from whence they now draw the designation we know them by. They had been preceded by odd and worrying reports from adeptus mechanicus exploratory teams and rogue trader flotillas in the galactic region, who, over the course of a solar decade, logged a disturbing number of worlds previously surveyed as having been reduced to lifeless spheres of rock. Where previously these planets had boasted verdant biospheres, they were now rendered completely barren. Remarkable that not even trace bacteria remained. No evidence was left that spoke to any cause of such catastrophes. As a regular balance of, for example, the function of the local star, or the fabric of real space, remained perfectly as expected. While these reports were forwarded with haste to both the exploratory general on Mars and the adeptus administratum on Terra, no further action was taken to investigate them, as the wheels of imperial and mechanicus bureaucracy grind slowly, and the intelligence likely went unnoticed in the data stacks of both organizations. The mechanicus would, however, pay for their negligence, as unto the ocean world of Tyran Primus, and upon their own facility there, the Tyranids made first planetfall. The hive fleet had been patient, as only an extension of the Cyclopean hive mind could be. It had spent the years previously stirring from the cold of the outer void carefully, ingesting the biomass of uninhabited worlds to rebuild its own reserves. According to impressive strength, it set upon Tyran, and there was nothing even the formidable defenses of an eastern fringe mechanicus outpost could do to stymie the tide of chitonous bodies. Despite this, and in a credit to both his order and species, Majos Varnek, nominal commander of the outpost, recorded as much data upon the invaders as he could, recognizing the menace of something entirely new in the annals of the Imperium, secreting the resulting codex in the deepest mining shaft of Tyran, and hoping the distress signals of the world would reach greater civilization. Majos Varnek and the last offenders perished in the face of the unstoppable swarm. It would be a full year before the Ordo Xenos, represented by Inquisitor Cryptman, were able to investigate the world, and discover the full horror of what had occurred there. The sacrifice of Tyran, however, would provide the Imperium with priceless data for the upcoming conflict, as the high fleet, now dubbed Behemoth, was making all haste to the worlds of Ultramar, heralding the beginning of the First Tyrannic War. Perhaps the advent of Behemoth, however, by a lot just investigate his magi, have posited numerous theories upon the first arrival of the great devourer into this galaxy. Our Imperium does not want for megafauna, and some of the more dangerously heretical amongst the learned of our empire point to the similarities between creatures such as the Catachan Devil, or the Fenrisian Kraken, as being evidence of Tyranid's seed entities, that may have become part of local biospheres across the Imperium, millennia, or even millions of years before Behemoth's arrival. While one cannot ascertain the veracity of this, records do corroborate the presence of Tyranid biophorms loose in the galaxy in two cases absolute, and one case yet to be determined, the Gene Steelers, of the moon of Ymngarl. First cataloged as an unknown Xenos race in 541, were extant at least 200 years standard before the arrival of High Fleet Behemoth, as well as scattered reports of similar creatures aboard the space hulks that drift the tides of the warp. Additionally, records declassified by Inquisitor Amberlee Vale of the Ordo Xenos as part of her archives on the life and career of the heroic astromilitarum commissar Caiaphas Cain, chronicle that as part of this commissar service on the ice world of Nusquam Fundamentibus, discovered hibernating Tyranid biophorms in the ice of the planet, dated by the Mechanicus, as having been over seven millennia old. This incredibly disturbing discovery would mean that the Hive Mind had its tendrils active in the galaxy, albeit in a much smaller, perhaps scouting capacity, since M34, only three millennia after the ascension of the God Emperor to the Golden Throne. Finally, and sadly impossible to confirm, is the case of the Legion of the Ouroboros. Pinned by the cardinal Myriamulus the Elder of Thracian Primaris, his is a history that speaks of a strange Xenos horde unlike any previously recorded, attacking the Helican Sector in M36. This Legion was spoken of in what was until the arrival of the High Flates considered lurid hyperbole, with chronicles of hideous winged beasts vomited forth from flesh sacks flung from the bellies of space-born creatures, redolent with the sort of imagery we have now come to associate with the descending swarm. An imperial crusade was rapidly mustered, and the Xenos cast out of the Helican sub, pursued and annihilated in a battle that lasted twelve days under the baleful gaze of the nearby Oculus Tereblis. The records were considered a work of allegory, or perhaps at most a chronicle of some sort of demonic incursion. Until the appearance of Behemoth, and more importantly, the later High Flates, sent imperial scholars scrambling for anything that could lend aid in defeating the great devourer. Investigation of the cardinal's accounts led inquisitors of the Ordo Xenos to examine the body of the warlord titan Mechanica Cranus, a renowned and ancient veteran of the Ouroboros War, which revealed distinctive bioplasma scarring in pyro acid burns that matched recorded effects of the more macro-scaled Tyranid bioweapons. It is also believed the space-wills chapter of the Adeptus Astartes fought in the conflict, and kept, as is their want, trophies very similar to Tyranid life-forms, including the so-called Kraken's Egg, although the chapter has, perhaps expectedly, not granted inquisitorial petitions to examine it. In the aftermath of the First Tyranic War, a conflict that deserves a record in and of itself, the Imperium believed that the Xenos' scourge had been exterminated for good, the extragalactic threat vanquished in the orbit of McCrag. Alas, would that it were so. It would be almost 250 years, but in 993, M41, the Imperium was faced with the horror of a new high fleet. Given the moniker Kraken, its pattern of attack was the polar opposite of behemoth, whereas the previous fleet had acted as one single swarm, a hammer-blow into a sole system. Kraken spread its tendrils over an impossibly vast volume, encroaching upon the Galactic East and cutting off entire sectors of the Imperium as a dozen different subsworms attacked simultaneously. The shadow of the warp, spread by these high fleets, cut off those regions from the rest of humanity, and there was little we could do save watch whole regions of the galaxy be swallowed in the darkening void. Then, scant years later, yet another threat. We had assumed, in our wholesale ignorance of the Tyranid race, that there were a threat emerging exclusively from the dead space beyond the Eastern Fringe, and that our defences ranged against them could be concentrated in that direction as such. Mistaken fools were we, as we observed a ghast as the tendrils of high fleet Leviathan struck the Imperium from below the Galactic Plane. The full magnitude of the threat these Xenos pose does not render you terrified perhaps this will. Whether by initial intent or simply due to the resistance our Imperium has posed to both behemoth and Kraken, the Hive Mind has sent its third apocalyptic swarm to circumvent our Galactic Plane itself, and strike at worlds at the very heart of our Imperium. With each year that passes more fleets emerge, smaller perhaps than the three greater Hives, but still deadlier than can almost possibly be imagined. Gorgon struck for the Tau Empire. The Drukhari stirred the ravenous hunger of the hibernating Hydra. Skyla and Charybdis move in tandem, tendrils devouring in concert like a dread helix. Molok ravages the regions around the ghoul stars. Oroboros, previously thought legend, now has reemerged, taking its name from the histories of the long dead cardinal of Thracian Primaris. Worse yet, we do not know how many more lurk out there in the dark. Has the Hive Mind decided our galaxy needs its total attention? Has that hideous intelligence sent its full might against us, or have we barely seen the beginning? Are the high fleets that scour our precious worlds of all life but the vanguard? Perhaps they represent a paltry percentage of the species' true number, a sliver of the Hive Mind's nearly infinite strength, and galaxies more await, biding their time, or are already approaching, trillions upon trillions upon trillions of chitonous bodies who shall not cease until we are rendered into nothing more than food to produce yet more of their profane kind? Is this the fate of our Imperium? Not to be rendered to fire by the hand of the arch-enemy, smashed under the fist of the green skin, scoured by the necrons, but instead as supper to some impossibly vast alien meta-predator. I say nay, I refuse to believe it. I have to refuse, for the alternative is to simply give in to the sheer scale of the foe we face. So I must spit upon the Hive Mind and its devourers. Let them come, let them taste Imperial bolt, let them perish under Imperial steel, let them test the resolve of human faith, for they will see that it cannot and will not be found wanting. Ave Imperator, Gloria, and Excelsis Terra. This video and this channel are made possible through the incredibly kind contributions of my Patreon subscribers. If you'd like to help support the channel, head on over to patreon.com forward slash Oculus Imperia. 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