Theories involving crossovers with non-Games-Workshop franchises should go here.
Due to size, this page has been split.
- Alternatively, the rest of this is true, but there are no loyalist Overlords—the tomb-world Lords awoke first as per another WMG somewhere on the site, and many, without contact with their superiors, reverted to earlier patterns. Some of these remain loyally C'tan-ist due to contact with the greater shards or just centuries of independence.
- Implied to be true. Transcendent C'tans regain their intelligence and personality and should be capable of acquiring a Necron Tombworld via subtle means or sheer might. There is also a certain Phaeron who is rumored to be a disguised C'tan shard since 5th edition.
- Glitch, or rebellion? Necrons might be fighting back against their oppressors the only way they can.
- Exactly. Their programming certainly doesn't cover sparing something which in millions of years could have developed into something sentient, so in the long run, the Necrons could be denying the C'Tan all future sources of food once they've expended the current galaxy's sentient population.
- Or maybe they just realize that the galaxy is a big-ass place. Having a large empty sector around your base of operations will strain the supply lines of any attackers while you can just rush out with your faster ships and harvest at will. There are stories of ships harvesting and not killing entire planets and taking them away, so it's possible that there are "farm worlds" full of captured beings being bred for harvest. We just haven't seen them because the systems around those worlds are full of necrons on barren planets, thus making it so no one wants to go any farther if they survive the experience.
- There's a quote that says the Necrons will enslave after they kill enough people.
It gets better because:All the Chaos gods except Tzeentch will die, and the Tyranids will enter the warp forever to feed off the energy, waging an eternal war with the Daemon hordes of the three dead chaos gods. This will eliminate these threats. Then, the Golden throne will finally fail, but the Emperor will resurrect. He will take command and slacken the Imperium's xenophobic, anti-innovation policy. The Imperium will form an alliance with the Tau, and then Tzeentch, the "good" chaos god, will join them, and the Emperor will redeem all traitors under him. The fallen Primarchs, Horus included, will be redeemed or resurrected. The Eldar will already have been wiped out by the dark Eldar, who in turn become extinct. The Necrons as they are now will be exterminated by the Imperium-Tau-chaos alliance, and their remaining tobworlds will need millenia to wake up. Many Orks will join the Imperium under "Warboss Emprah". The ones who don't get wiped out from too much fighting with the alliance and each other, until the last independent warboss has a prophetic dream and takes his WAAAGH! off on a crazy quest out the galaxy. They never come back.
It then gets worse because:The factions and species of the alliance trade technology to build new weapons, and get ready for the arrival of whatever the Tyranids are running from. It arrives in the 56th millennium. Fortunately "Warboss Emprah" just achieved something resebling enuff dakka. The setting gets Grimdark again because of this war between the new arrivals, the now-fully awakened Necrons and the alliance. Cue Warhammer 55,000.
- May I ask, why that specific year? Is there something in the lore that states 14,000 years? If they want to make a sequel series (set thousands of years after to get more money) why not Warhammer 50,000? 55 is just an odd number to use.
- The Ossumodula (Bone growth), Preomner (poison prevention), Oolitic Kidney (again, prevents poison), and Biscopea (Muscle growth) are taken from Orks.
- Betcher's Gland (Acid Spit), Progenoids (Geneseed collection), and Omnophagea (Learning from Eating) from Tyranids.
- Black Carapace (Greater armor interface) from Necrons.
- The Tyranids are just now showing up, 10,000 years after the Emperor created the Space Marines. For that matter, Emps had been isolated on Terra for 10,000 years and didn't have access to any aliens to take bits from.
- You're right, but for the wrong reason. Chaos's natural state is an endless conflict and disorder, and this manifests by most of the Dark Gods' time and attention being spent fighting each other in the Great Game; a conflict that naturally can't end and can't have any permanent victories. The cycle of conflict can be broken by an outside force acting on it, and the Emperor was becoming that mutual threat/stabilizing element, and the Chaos Gods stopped fighting just long enough to bring him down together. When Big E was cut down, the Chaos Gods went back to the the Great Game, only occasionally putting some attention on realspace. An individual Chaos God does take swipes at the Imperium and Emperor, but in the end, it won't feel too torn up if that problem goes away and loses a persistent secondary threat, not when it's main three enemies are still around and right on its doorstep. Chaos's victory was hollow in that all Chaos did was preserve it's own status quo, it didn't evolve, unify, or change in any real meaningful way. Chaos is still getting stronger each day though, and one day it will overwhelm the Imperium and the rest of the forces still in realspace.
To boot the Imperial Council of Terra is portrayed as horrifically racist, openly planning the genocide of most of Earths racial minorities (predominatly Blacks, Asians, and those of middle eastern decent). The near overwhelming majority of seemingly exiled minorities live on off world colonies termed by the game itself as "Dark Worlds".
Basically imagine if our current Warhammer game had lines like "Kill the Ni**er, Purge the Chink! Games Workshop would have a far smaller fanbase. GW must have realized that either by intention or accident they had made Klu Klux Klan 40k and promptly never made another version of the game. Although oddly enough both miniatures and original rule books are still sold on a seperate website.
However if you include this backstory (which I'm calling 40k 0th edition) into current Warhammer canon it shows that in reality the great Emperor of Man never really existed and was only a monumental piece of propaganda created by the High Lords of Terra either to terrify or inspire the common Imperium citizenry into a fanatical devotion to the racist lords of Terra and to the common ideal of "Imperialism" itself.
However this also does not completely mean that the Emperor did not exist. There are only 3 possible scenarios of how the Emperor could exist in within current canon which are...
1. The "Emperor" is only some poor fanatical bastard who willingly sacrificed himself to be plugged into the golden throne to be used as a symbolic effigy for future generations or...
2. He was some even poorer bastard who was murdered by Terran High Lord order then placed against his will in the Golden Throne as a braindead vegetable for over 10,000 years. This would mean that everything from Rogue Trader to now is complete Imperium bullshite. The Horus Heresy, Warp chaos, traitor marines, Chaos gods all Never Happened. And finally...
3. The "Emperor" was either one of the lords of Terra or an unseen Imperium noble whom literally had both extreme delusions of godhood and enough Ax craziness to start his own "Great Crusade" to overthrow the original lords of Terra and place himself as"Emperor" of all mankind.
He creates 20 genetically modified near clones of himself whom he calls his "sons" and for paranoid reasons that his "enemies" were out to get him scatters them across across the galaxy. Meanwhile the "Emperor" goes about creating a North Korea like Orwellian society along with a religious cult of personality with his most fanatical followers declaring him "God Emperor".
After several years later the now "God Emperor" retrieves his sons and orders them to be given massive amounts of possibly crippling enhancement surgery in order to become newer upgraded versions of space marines. 2 of the "Emperor's" sons die in the process. The newly created space marines lead the imperial armada across the galaxy for the second stage of his "Great Crusade" burning Xenos worlds and purging human colonies who don't align themselves with the new "Emperor"
However as was stated above this Emperor is Super Robot Hitler levels of racist. With every new triumph the "Emperor's" madness and lust for power grows by the minute. With every success he demands more minority purging and more alien genocide and more godlike devotion to him. Finally one of the "Emperors" sons have had enough of his fathers and the Imperiums insanity
Horus leads nine space marine legions against the "Emperor" and the imperial fleet. This war is known originally as the "Horus Mutiny" or Rebellion (millennia later this changed into the more religious version of "Heresy"). Horus allies himself with 4 native Warp space alien species originally targeted for exterminatus they are later termed by the Inquisition as "Deamons" and "Chaos"
Horus is ultimately defeated but he somehow manages to allow the survivIng marines to escape into warp space. He also manages to nearly kill the "Emperor", However the Emperor has a final ace up his blood covered sleeve.
Years previously the Emperor becoming increasingly obsessed with immortality due to his self believed godhood had secretly ordered the creation of a life support system never before seen as it would keep its occupant alive indefinitely. As the imperial madman plugged himself into his "Golden Throne" he made a silent vow to destroy all his enemies and finish what he started.
And so the mad emperor sits on his throne keeping him in a state of slow physical decay leaving him a living corpse for 10,000 years possibly within a state of unimaginable insanity that possibly could rip the very universe apart. While the seeming death of the "Emperor" should have ended his mad reign his deathless sleep only appeared to reenforce it. The Imperium went on a slow decay of technological, social, and mental collapse.
- there just a problem, Tzeentch is the God of change, think when you have hope to the future, it's because you want something to change, like if you lived in a crapsack world, you hope for the future being better...so you want change...THIS IS THE PROBLEM...
- ...gods of selfishness? It says everywhere that isn't Imperial propaganda that the Chaos gods have benevolent aspects, and besides, ambition is morally neutral. It's what your ambition is for that can be good or evil.
- Yet the Emperor Himself is a God of Hope, and he is now a rotting corpse...
- No he isn't. He's just a hyperpowered psyker.
- You're wrong, he is actually an example of mankind if we had evolved as the Old Ones did, which does make him a superpowerful Psyker, but also a nascent Warp Entity.
- No he isn't. He's just a hyperpowered psyker.
- To be fair, most of the xenos were incalculably cruel alien overlords. There's no chance of getting along peacefully with Orks or Dark Eldar. And the Emperor didn't build monuments to his vanity, that was mostly the Word Bearers. And he put a stop to it. It's also natural for rememberancers and other records to glorify the Emperor. He was basically the greatest human to ever live.
- Pretty sure I remember reading somewhere that it was the Mongols, not the Christians, whose actions caused the giant mass of psychic rage and aggression to form into Khorne... Also sure Games Workshop has implied that the Abramahic Religions where all made by the Emperor, in attempts to unite humanity through laws then love and finally discipline.
Farsight has looted a Necron tomb world. It's probably best that he doesn't find out.
Because of this, he took on a new model for the Ottoman Empire which he helped build, as Suleiman, and took work to rework the laws and civil underpinnings that had previously worked, but at the same time changed some tactics used, and with it observed the Janissaries, who he would later use as models for the Space Marines, and also looked over matters such as taxation, which he would later similarly adopt for the Imperium.
But as Mustafa Kemal Ataturk, he felt the religious model of state did not work, and broke it into something else, and observed Turkey as it was, and used the model of secularism along with reforms done as Justinian and Suleiman, and worked them into one state for his ideal of the Imperium.
Fast forward ten thousand years and he got so good at killing them that Tyranids were forced to flee. Sadly, as usual in W 40 K-verse, his vision was a Self-Fulfilling Prophecy and by trying to protect the Imperium from Tyranids, he instead herded them there for Great OMNOMNOMNOM.
Malcador was born Yeshua of Nazareth, and the Emperor, when he first met him, was known as Judas Iscariot. They cooked up the idea of trying to create what would become Christianity as something of an experiment on the power of belief, and basically ran a con. All those miracles? Either Yeshua/Jesus/Malcador's own psyker abilities, or his buddy Judas pulling off bigger tricks from the background. The nascent religion needs a betrayer to curse, and a martyr who comes back from the dead for a central figure? Pretty easy to pull off when when the martyr can't actually die under normal circumstances.
- I believe it's almost-canon that it was the Emperor who was Yeshua. And out of sheer curiosity - why would he be Judas?
- Mostly because what we see of him in the Horus Heresy novels shows him to be way too much of a bastard to be Jesus, even as a con, and being the man behind the man instead of the man himself fits the way he tried to do things before he actually took over.
- No, being the guy in front doing things is exactly the God-Emperor's MO. He possesses massive charisma sufficient to charm basically anybody, so the more candid depictions of him in HH should be taken as just him letting his guard down around people he was comfortable with. If anything, Malcador would be Judas, as being the man behind the man is literally his entire schtick. We're talking about the guy who founded the Administratum and what would become the Inquisition.
- Remember, he only did that after the society he painstakingly created via manipulating society basically crashed and burned around him.
- Imperium: 40, 000 years of stagnation and lack of innovation, and turning its back to new ideas in exchange for worshipping a dead god and throwing countless lives for nothing (Sloth)
- Eldar are Lust. They birthed the sex god Slaanesh after all.
- Orks are Wrath. They want to slaughter every other species, but when there are no others to fight, they immediately riot between each other in brutal combat.
- Chaos is Greed. They want to corrupt everything. Most Chaos followers are often driven by a selfish desire to acquire more Power.
- The all-devouring Tyranids are Gluttony.
- The Necrons are Envy. Remember the backstory: the reason why the Necrontyr became the way they are was because they Envied the Great Old Ones and their Immortality. That was the reason why they forged the contract with the C'tan to become Immortal Robotic entities.
- And finally, the Tau are Pride. Sure, they have the innovation tradition that the slothful Imperium lacks, but then again, they were confident that they had the best philosophy to apply to the universe, and if anybody refused to accept the Greater Good, they committed orbital bombardment and mass brainwashing, just to make them believe that they were right. Other wiser races, such as the Imperium and Eldar, often engage in deconstructing the Tau's naive philosophy in the context of the reality of the 41st Millennium.
- Oooh... It's a Genius Bonus even if it's unintended.
This is the real reason the man who would become the Emperor stood aside for most of the Age of Strife - he wasn't alive for the vast majority of it.
- Possibly overlaps with the "Tzeentch is one of the Eldar's greatest allies" WMG on page 2 of the archieved WMGs.
- The Thunder Warriors were culled by the Adeptus Custodes. The Emperor probably made the Custodes first, then after having an army of ageless Super Soldier bodyguards, started mass-producing an army of barely-stable psychotic berserkers.
- A revived Guilliman spoke with the Emperor, unless the spirit is masquerading the Emperor probably jossed.
The carcharodons are said to come from "the black void of space beyond the farthest reaches of the galaxy", and what animals are most well-known for chasing things out of an area? Sharks.
Because it's too perfect and too Tzeentch to not be the case. War Zone Fenris appears fairly pointedly to not be related to Abaddon's current Black Crusade; methinks that the possible destruction of Fenris - or at least sending the Wolves packing - will place them in line to help hold off the Crusade from the greater Imperium. After all, a world where Chaos wins is one Tzeentch is likely to consider stagnant and dull, and that doesn't tie with how he likes to play his games. And it would be be so very like him to even screw over the Legion that are begrudgingly in his service.
- Doesn't seem likely unless they reveal that The Great Rift opening up in the wrong directions is caused by War Zone Fenris's influence.
- The Lion received the Emperors honor, which made him level-headed enough to be a tactical genius as well as diplomatic and sincere enough to lead men effectively. Unfortunately, this also gave him a personality flaw which made him make questionable decisions on occasion.
- Fulgrim received the Emperors desire, which made him seek perfection in all things and gave him the capacity to appreciate the beauty in things others would consider hideous. Unfortunately, wanting to push his own boundaries made him susceptible to doing questionable things in order to do so.
- Perturabo received the Emperors creativity, which made him seek democracy and diplomacy as alternatives to rule of force and warfare, and made him a genius architect. Unfortunately, daddy didnt want a diplomat, and forcing him to be a siege engine gave him an inferiority complex to Dorn, as nothing he was forced to build could ever be as good as something Dorn was made to build.
- The Khan received the Emperors wanderlust, which made him an ideal crusader as he always wanted to see what was beyond the next horizon. Unfortunately, he didnt care too terribly much about his brothers and their problems, as those things only served to keep him from moving forward.
- Leman Russ received the Emperors instincts, which made him handy in a tight spot and able to see to the heart of a matter. Unfortunately, this left him relying less on rational thought, which resulted in his charging into places without contemplating why.
- Rogal Dorn received the Emperors fortitude, which made him psychologically stable enough to withstand just about everything that could be thrown at him. Unfortunately, this stability made him utterly inable to use tact, as his mind just wasnt flexible enough in social situations to realize its benefit.
- Konrad Kurze received the Emperors insight, which made him understand human psychology and gave him his visions of the future. Unfortunately, understanding the psychology of humans combined with his ability to predict the future made him something of a neurotic mess who sought to impose order on the chaos through whatever means were necessary.
- Sanguinius received the Emperors compassion, which made him probably the most likeable Primarch and gave him an appreciation for the humans he was supposed to be championing. Unfortunately, this left him unable to destroy a once dearly beloved foe, and led directly to his fall.
- Ferrus Manus received the Emperors diligence, which made him extremely hard-working and efficient at the tasks he set his hands to. Unfortunately, this made him distant from all but very few of his brothers, and prevented him from curtailing the cybernetic excesses of his Legion.
- Angron received the Emperors courage, which made him able to stand against insurmountable odds when he knew the cause was right. Unfortunately, that same courage turned into recklessness when combined with the Butchers Nails, leading him down a path of unrelenting fury and bloodshed.
- Guilliman received the Emperors patience, which made him able to think long-term and create vast strategies which are still in use in the 41st millenium. Unfortunately, he came off as egotistical to those of lesser patience (that is, everyone else) and his tendency for detailed planning left him holding the bag when unexpected events occurred.
- Mortarion received the Emperors self-reliance, which made him the toughest, strongest SOB out of all of the Primarchs as a rule. Unfortunately, he considered anyone not strong enough to make do on their own less than human, and he extended this thought to anyone who used the Warp to accomplish things, making him view the Emperor as a hypocrite.
- Magnus received the Emperors curiousity, which made him eager to study and learn all that he could about everything. Unfortunately, this is Warhammer 40K.
- Horus received the Emperors ambition, which made him the ideal Warmaster to take the Emperors dreams to the stars. Unfortunately, one cannot have ambition without a certain amount of vanity, without believing that the things youre striving for are, in a sense, owed to you. Horus loved the adoration he received for being Warmaster, and couldnt conceive of his fathers vision of an Imperium which didnt need him or his brothers as leaders anymore, leading him to oppose the Emperor in an effort to claim all the glory all the time. Much is made of how seemingly easy it was for Horus to be convinced to side with Chaos, but in truth all the Ruinous Powers did was provide him with backup and justification for what he really wanted to do anyway.
- Lorgar received the Emperors faith, which, as the Emperors weakest and most repressed personality trait, made him the physically weakest Primarch, but the one who had the most potential for empathy. Unfortunately, the Emperor wanted nothing to do with faith and refused to acknowledge that humanity needed some level of belief in a higher order, thus setting up Lorgar to be the instrument of his downfall.
- Vulkan received the Emperors humanity, which made him the Primarch most concerned with the little people and an absolute beast when it came to defending them. Unfortunately, he didnt really believe that he was actually worthy of commanding people, and thus while a good commander, he was too kind-hearted for war.
- Corax received the Emperors romanticism, which made him into the quintessential Underdog who used guerilla tactics and small, elite forces to bring justice to larger, stronger forces of evil. Unfortunately, this is 40K.
- Alpharius Omegon received the Emperors mind, which made them scheming bastards par excellence, but also made them think that they were right all the time and that they were better than everybody else.
- Could be a standard design given the Centurion armor.
Consider this. The stories of the Emperor's origins, like him stealing power from the Chaos Gods or being created in a ritual by ancient shamans, are not considered to be definite canon anymore, so we do not know for sure where exactly he came from. However, we know that at least one race had a very similar individual: the Orks, who had their own demigod with incredible psychic power, the Beast. About his origins, nothing is known at all. We have precedence of powerful races (presumably populous and psychic enough to create a large presence in the Warp) inexplicably giving birth to God-Emperor figures.
Perhaps the creation of demigods is some sort of natural process in the Warp, caused by the collective psyker energies of mortals coalescing. If that is true, then the first race (other than the Old Ones) to undergo that process would be the Eldar, who would create their own equivalent of the Emperor and the Beast. These beings would be easily powerful enough to be considered gods, yet due to being born in the Materium, they would still have minds and bodies comparable to mortals - which is exactly what the Eldar gods are. Of course, due to their psychic power, they would be inherently tied to the Warp (much like the Emperor is able to create Living Saints and maintain the Astronomicon) and even able to enter it, especially in its calmer pre-Slaanesh state, which would explain them interacting with Warp entities.
The only problems I see with this theory are the myths of Eldar Gods creating the Eldar and Ynnead, which is an explicably Warp-based entity with no presence in the Materium. But then again, myths are not always true, and if the Eldar Gods were born while their race was still living in caves, and guided them throughout their early history (like the Emperor, but more overtly), the Eldar would basically see their origins that way - "We used to be primitive animals, and then the gods gave us wisdom and made us what they are now.". As for Ynnead, he seems to be a unique entity, so him being a Warp entity and all other Eldar gods being ascended mortals is plausible.
This theory opens up the possibility of other races creating their own God Emperors. The Necrons are out of the question because they have no Warp presence, and the Tyranid Hive Mind is already essentially a Warp deity, so if any demigod appeared in their species, it would be either absorbed or become subordinate to it. That leaves the Tau, which, who do have a weak Warp presence and are rather populous. Could a God-Emperor appear among their kind?
Perhaps the Emperor was a proto-Tzeentchian. Since the Warp is beyond space and time, it is possible that an avatar of Tzeentch or a Lord of Change was sent back millennia before during the genesis of humanity. During this time, Humanity was just another animal, and the weakest in the food chain, hunted down and murdered by countless apex predators, from lions to bears, if not dying from numerous diseases (it was from this era that the first Chaos Gods such as Nurgle began to gestate). But while most of mankind was contented with this savage lifestyle, there was one who was dissatisfied, and wanted Change. Change, where humanity, instead of being just a failed species of ape, had the power to Change the World around Him to his own Will. Thus, when the child made contact with the aforementioned Lord of Change, they made an Unholy contract: Humanity shall gain Knowledge, and therefore the capacity to Change the Natural World through their own Intellect, a Dominion that which Mankind sees fit. This was where we get the story of Genesis: Adam eating from the Fruit of Knowledge, which both benefited and damned humanity as a whole, the knowledge of civilizationand dominion over the natural world in exchange for the loss of happiness and soul.
"Adam", as we would call the Emperor, and the person who contracted with the Lord of Change, was initially loyal to the God of Change, by posing as numerous beacons of Hope throughout Human History. This is where we get "The Emperor was Jesus" meme. Humanity developed and some of the Chaos Gods made their first appearance (Nurgle during the Black Death, Khorne during the Mongol wars). "Adam" used Sorcery against the Void Dragon to imprison it on Mars, because the C'tan are weak against Warp powers. Then, he guided an ancient Order of scientists and alchemists persecuted by the Roman Catholic Church, the so-called Gnostics or Illuminati, to engineer the Renaissance and show Humanity the path to Hope and Change once more. Unfortunately, the new technology developed by this Hope in Science and and Progress, instead of benefiting Humanity as a whole, were used as weapons and inventions humanity can use to destroy itself. This reached its peak during World War II, when a rival Chaos Cultist named Adolf Hitler used the products of Change to almost destroy the world. This was where Adam realised that Tzeentch dicked him over; Hope and Change, his virtues, were not the key to mankind's survival. Thus he plotted his Rebellion.
During the Dark Age of Technology, the era of Change and progress when Humanity has developed the capacity to harness and transverse the Warp, Adam constantly used his former daemonic gifts to plot against the Daemon Lords. This was where, in some sources, he discovered the planet of Molech. Molech contained a Gate that directly led to the fortressess of the Chaos Gods themselves. Adam, due to his continuous plotting against Tzeentch, defeated his old master in a game, outsmarted the more stupid Chaos Gods (Nurgle, Khorne and Slaanesh), and stole portions of power from a source claimed by the gods as their own. He would use this power to evolve himself and create the Primarchs. This would earn him the ire of the duped/defeated Ruinous Powers, who consider him as some sort of usurper.
This was why, in the establishment of the Imperium of Man, and during the Council of Nikaea, the Emperor, though a Tzeentchian himself, whose philosophy was Hope and Change for Mankind, could not allow Magnus the same luxury of knowing the prospects of the God of Change. The Emperor feared Magnus would descend to the same path he had, a puppet by the Master of Fate. This is the reason for the Imperial Truth and the policy of State Atheism; The Emperor knows he is a Daemon Prince of Tzeentch, but he cannot let others suffer the same fate, so better to keep everyone ignorant. Untimately, despite his efforts, his old master triumphed, and as the ultimate form of torture towards his rebellious student, warped his ideals of Hope and Change into his own worst nightmares, a totalitarian dystopia obsessed with killing itself.
1. the Primarchs are meant to be vessels for the C'tan to download themselves into, allowing them to finally control the warp
2. the Imperial Truth suppresses belief, calming the Warp.
3. controlling both the Webway and the Astronomicon, the C'tan will control all FTL travel in the galaxy
4. with all technology coming out of Mars, all of humanity's tech will be tainted by the Void Dragon
5. the Golden Throne is actually C'tan tech, the sacrifices to the throne are actually keeping the C'tan alive/empowering them.
The ultimate goal, if Chaos had not interfered, was to repeat the process of creating the Necrons. Some of the traitor primarchs may well have realised the truth, and decided that the Enemy of My Enemy Is My Friend.
After the immaterium was fucked over by the War In Heaven, the presence of sentient minds perpetuated its chaotic nature indefinitely. Thus, the Old Ones made the Tyranids to remove all sentient life from the galaxy if and only if Chaos started getting out of hand - that is, they didn't want to kill everything, but they wnted even less everything enslaes to the Chaos Gods. The Tyranids were stationed outside the Galaxy and made a few harvest runs every now and then to restock on energy and mass, and the seeding of deathworlds with Tyranid-Adjacent bioforms was nothing less than the creation of a surveillance system - each animal on those worlds was, essentially, a piece of an optical telescope array that allowed the hivemind to maintain total glactic surveillance, to ensure the warp rifts didn't git out of hand. The Eye of Terror's appaearence began waking the hive fleets from dormancy, and now that the Cicatrix Maledictum is there it's time for the cleaners to, er. Clean.