WHY DID THE LOST PRIMARCHS GET ERASED? WHAT MISTAKE DID THEY MAKE?

Hi all Rho here!
Today we discuss the Lost Primarchs, as we ask the question just what did they do, that forced the Emperor to erase them from existence?
General Spoiler Warning to begin! As we will be discussing events from across the Warhammer 40,000 universe! So you have been warned!
Games Workshop does not endorse or support this video. All views and opinions expressed in this video belong to Wolf Lord Rho and in no way reflect the views or opinions of Games Workshop Ltd.
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Music belongs to Wolf Lord Rho.

[@leonardovergara5620]

They found Victoria's Secret.

[@jkee9760]

One found secrets on the clintons and the other told hank hill he likes charcoal.

[@johncherrybone4835]

@@jkee9760 I don't know witch will get u killed faster

[@TheVexusKnight]

Da faq

[@reina4969]

So they were one of the few WH fans that reached puberty?

[@plasticspoon60]

They tried to out pizza the hut.

[@Siege181]

In my head cannon, I imagine that one of the lost Primarchs had his brain usurped/corrupted during the Rangden Genocide. This would explain why the campaign was so hard fought and why records of the genocide were expunged.

[@vortex_1336]

Yup. Was corrupted by the Rangdan and possibly killed the other lost Primarch in a betrayal. A Primarch joining a xenos species would never be allowed to be publically known.

[@Cody18pl]

@@vortex_1336 I am also of the opinion that for the emperor the alliance with xenos was the greatest betrayal and he decided to wipe out at least one legion and primarch.

[@vortex_1336]

@@Cody18pl The Rangdan most likely could mind control or physically corrupt other organisms. Meaning there wasn't an alliance. More of an infection.

[@adrienwatson2179]

This is the most likely scenario imo. Especially since the Dark Angel's were called in to "Exterminate" and the Space wolves to "Execute" as Leman Russ and The Lion have bith said respectively. Would take both of them to do the work... as the 2nd Primarch was known to have been able to "Conquer worlds by himself" So powerful indeed

[@NecrosAcolyte]

Xenocide. Not genocide

[@stupidfrog2205]

"What did the lost primarchs do wrong?" They used third party parts in their legion and breached the IP on KZbin

[@jason.larsenthedanishgreek1226]

You mean they did not buy into the CNN narrative

[@MajinOthinus]

@@jason.larsenthedanishgreek1226 What?

[@voytek6520]

@@jason.larsenthedanishgreek1226 They lost Afghan, honor and comitted mass suicide

[@VkmSpouge]

Or worse still; they were using 3D printers to produce vehicles for their legions.

[@stupidfrog2205]

@@VkmSpouge the worst crime possible in the GW's Imperium

[@Ceiling_Gato]

My headcanon is that one of them landed on an alien world where he was raised by a Xenos race and then refused to blindly genocide aliens. Basically a Primarch who was so good and idealistic that it got him killed.

[@plasticspoon60]

Thats my favorite theory aswell. If one or both sided with a xenos empire against the emporium of man that would get them purged. Maybe one convinced a loyal son to join them.

[@MrFallenone]

Or on a planet where xeno and man lived in harmony. Very haram. Had to be erased.

[@allways28]

I’ve thought that one was basically a more informed Magnus, who knew of the warp and the chaos gods and greatly rebelled against the emperors imperial truth. The emperor then had no choice but to eradicate this primarch because he would have essentially spilled the beans. Ironically if E had been more honest about the truths of the universe to begin with things may have been a lot different …

[@kenn9283]

@@MrFallenone that’s what I like to think. Something like warhammer fantasy where man and xeno work together against a threat and become allies.

[@adrienwatson2179]

Unlikely Since the 2nd Primarch had "Conquered worlds by himself" and the other Primarch was sent on missions to the edge of the galaxy in areas that were overflowing with Necron tech (He was sent to investigate) Most likely one occurred in the Rangdan Xenocide, since the Rangdan could control minds.

[@davidk6269]

What mistake did the two lost primarchs commit that lead them to be erased? They violated the GW IP policy. There's no coming back from that. ; )

[@surfer301]

bet they used 3d printers lol

[@lyndonjohnson5063]

Feel to chaos and one a whimp and didn't want to kill this is lore

[@voytek6520]

They stood against GW greediness!!!!! As we all must!!!💪💪

[@voytek6520]

@@leyland610 Solid

[@RedwolfDogrocket]

TTS SHALL LIVE AGAIN *stomp-stomp*

[@velociking20industries42]

What if the emperor did enact a massive cover-up, lying even to his sons about why their brothers were expunged, perhaps even implanting false memories in russ’s mind about the purging of those primarchs. I mean, if two full loyalist legions were to pop up out of nowhere, that would be a massive reinforcement to the imperium. And since each primarch/ legion was designed to fit a specific role, perhaps the lost primarchs were designed as last resort super weapons, and had to be exiled and expunged to protect them from the chaos gods interfering with them, and taking them as pawns.

[@andrewniehoff8612]

I like that idea, a good plot twist and the Emperor is not above lying. Could you imagine if that was true and they did come back? "Father! We have come to warn... "WHAT THE BLEEP IS GOING ON?!

[@adambman2]

I was thinking along these lines as soon as I started watching the video. Without dismissing the other options, for this theory, Russ pretending to have executed them and keeping the secret of the cover up (however much or little he knew) would prove his loyalty as much as if he really had dispatched those two brothers. It's not like Russ hasn't played the braggart before, though a somber mood surrounds these events for him, of course.

[@jagnestormskull3178]

I can see him doing that for one Primarch, but two? It takes a lot of power to create a Primarch; redundancy is only a good thing in very few cases under those circumstances (Dorn and Perturabo both being expert architects, for example, may be a good choice because they're building a galactic Imperium), but having two ultra-expensive MEGAweapons in addition to all his other superweapons (the Ordo Sinister, the Ironwing's super-robots, etc) just seems like a waste of a Primarch.

[@yuripleminik3807]

That would suck

[@ericmiller254]

THere is a short story where Dorn gets his memories back. "The Chamber at the End of Memory" In this short story he gets his memory back, and claims that what big E did was just. Whether or not those memories he "regained" were real? Who knows

[@johnnys8393]

"...The emperor is willing to overlook things to benefit his crusade...the damage done to Angron"...I should bloody think so! The butchers nails notwithstanding; it was the emperor that damaged Angron the most by whisking him away from his friends instead of saving them as well as Angron!

[@QixTheDS]

It’s things like that which make me think he had planned a civil war from the beginning. Whether it turned out how he wanted I don’t know.

[@northernalien761]

@@QixTheDS I agree, I believe he had to bring the gods of chaos out to ascend to godhood himself. It was the plan all along and he needed to divide his son’s in a precise way.

[@henryviiifake8244]

For someone so impossibly clever, the Emperor is sometimes so implausibly stupid. He could have saved Angron's friend with a _literal_ wave of his hand, but _chose_ not to. That's all he had to do for Angron to at least have a reason to respect him.

[@joshw9277]

@@henryviiifake8244 or perhaps it was all part of the plan, having a Barely sane attack dog around has its advantages, look at the Knights of Blood sacrifice to hold back the Tyranids AND Khorns hordes. Even The Rout and the Blood Angels have their pragmatic limits, while the World Eaters were berzerkers even before Angron.

[@arthurtitangenlpendragon]

Yeass~~. Blame daddy for your incompetence. Ooh~ my gracious blamer.

[@deathbeforedishonor6523]

I really love the idea that the 2 lost Primarchs have been battling and stemming the tide of the Tyranids. Them coming back with the stories and information regarding it would be mind blowing. The need for a full scale invasion to be braced against or full scale invasion to be launched into the Tyranid occupied space to stem the tide before it happens would be absolutely amazing.

[@URKCEHinoSuu]

Considering the vast distance to be covered between each galaxy, and also the fact that there's an entire main body of the tyranids headed towards us first, we'll be the ones who will have to brace the full scale invasion of the galaxy first. And I bloody don't like the fact that the 3 main hive fleets we've seen so far, namely behemoth, kraken and leviathan were merely SCOUT forces, we're fecked, even if the entire galaxy fought as one. That's one war we might not win. That this galaxy might not win. But hey still, this tyranid theory is really great. 👌

[@MWH12085]

One theory which I kinda like is one of them is the actual hive mind. Seems plausible since it kinda rips off Starcraft and thats how GW rolls. Games Workshop- We'll rip off any IP, but God help you if you dare try and make unlicensed stuff of ours.

[@DaCrazyMofo]

@@MWH12085 more likely that it's either the outsider or the old ones

[@DaCrazyMofo]

@@MWH12085 tyranids look like dinosaur bugs after all 👀

[@squishymusic9723]

@@MWH12085 Starcraft and Warcraft was actually once warhammer, until GW pulled out of the game. They cant rip off that IP since it was theirs 🤣

[@Leptospirosi]

- From the fears of Sanguinius expressed to Horus, we know he was in the same boat with at least one of the two lost Primarch, unless he was referring to the Thousand Sons culling being discussed untill Magnus found a way to stabilize their geneseeds and keep them going. - From the fact that Maguns was still alive and kicking despite the flesh change, if the genetic line of one of the Lost Legions was compromised, we know it must have affected at least one of the two Primarch, not just the legions. It might well be that the Primarch of the doomed Legion refused (as Magnus himself much later) to submit them to be destroyed and fought against the Empire, which could relate to Russ being involved. I guess the other Brothers would see the necessity for culling the Legion but still could not condemn their brother for trying saving his sons. It is interesting, throught that Magnus never brought out the story as it would very closely reflect his own story arcline, particularly during the siege of Terra. Being the first Primarch to fight against the Empire would justify his erasure from the imperial records as it would be seen as Big E fault. - We may infer that Leman Russ could be involved in the missing of at least one of the two Primarch, as we know, from Sanguinius, something did not end well for at least one of the Legion and Russ could have been the executor, but this is just speculation as the infight with other legions could refer to the Dark Angels, the World Eaters or the Thousand Sons themselves as they campaigned with the Space Wolves and fought them over a leftover library. - Fulgrim briefly speaks of the Primarch of the second Legion describing him as not very verbal, unremarkable and without much of a sense of humour. - We also know Horus and other Primarcs accused Malcador for removing the statues of the fallen brothers meaning that he (as Fulgrim) was not mind wiped on the subject. We also may infer that whatever happened to the two Primarchs was not considered a crime: they were still considered as Brothers, not just traitors. Furthermore, had part of the Legion and their Primarch been tainted by chaos, the leftover of their Legion would never have been melted to other pure legions. They had to be completely untainted for that to happen as we know how vulnerable gene seeds can be to chaos influence. - We have hints that at least one of the two legions was involved in the Rangdan Xenocide during the Great Crusade, where even the vast Dark Angels Legion was left crippled. And still, why, if a lost Primarch was killed in the Rangdan war, his men were not integrated into the Dark Angels which had suffered horrendous losses in the same war?Why the Legion was technically dissolved as we know it did not happened to the Blood Angels? Why the Primarch fallen while fighting the enemies of the Empire was redacted from the records and his name forgotten by order of the Emperor? - We know that something unspeakable happened, but we know a lot of Legionaries were just mixed with the Ultramarine and the Imperial Fists, from at least one if not both the missing legions, so we know whatever affected the Primarchs involved was local and not a complete Legion failure. Dorn at the siege of Terra laments not having the two brothers on his side, so he remembers them but not having their Legionaries among his own men; feels weird that the only wiping was related to the legions being melted, but why mind wipe Papa and Grandpa Smurf on such an important subject which may have consequences on their Legions in the future? - It "might" be at least one of the lost Primachs fell during a full head-on clash with a demonic horde, in an era when it was forbidden knowledge as we know Horus did know nothing about chaos at the time of the contact with the Interex Comune, yet it would make sense to have their statue in prominence as they fell defending the Empire against overwhelming "unspecified" enemies rather then have them being forgotten by humanity. Something fishier happened but not something that could have them discredited in the eyes of their brothers: something that mightly pissed of Big E but left a bitter taste in the mouth of many of the remaining primarchs, I guess. I can almost hear the chrone voice of Malky saying: "Be bad boys and you will end like those two!" - It is finally possible that the two lost Primarchs died fighting each other, something not admissible and for that they were expunged from the records in shame. This could explain the quote from Russ about Legion taking on other Legions on a large scale before Prospero. This would also explain why the other Primarchs were so ashamed at the possibility of fighting another brother. If both Legion lost their Primarch and because of the crippling losses and bad blood between them, it makes perfect sense for Malcador the decision to wipe their minds and their Legions identity by melting the survivors among existing legions. Bringing them back to full numbers could only mean keeping the madness going as the lost of the Primarch would fixate the survivors into eternal hatred. - BIG P.S: we don't know who and when was "The Angel" despite we know he was active across the galaxy and not just on Terra, destroying a planet for not being pure enough, before Exterminatus was a thing, alone and in a single night, to the point that the Emperor had to put him in stasis using a subterfuge as it was probably not in control of his son any more. Quite a messy family with a lot of skeletons hidden in the closet.

[@em4rtzz]

what book has that part about he angel and putting him in stasis?

[@Leptospirosi]

@@em4rtzz I think it was the novel "Death of an Angel". Big E uses a piece of Demon flesh to lure the Angel into the stasis vault and seal it as the dude was getting rampant killing anyone not "pure enough" and going genocide on several planets. I guess Big E himself thought the Angel impossible to subdue even for himself. Technically it was a murderous anathema for anything tainted by Chaos, a "Chad" Primarch of the Primarchs on BIG steroids from which the known ones brought their personal traits. Aspect and wings for Sanguinius, Psychic might for Magnus, stubbornness for Dorn, murderous retaliation for Kurze, savagery for Russ, fanatism for Aurelian... You get the figure of why it was not a good idea... 🤔 Somehow I imagine the "doomsday device" installed by Vulkan into the throne room could be just a calling device with the automated message "Hey Son, time to wake up: daddy needs you!"

[@dreadbringer]

Ah the infamous primarch 0 though i dont know if its "canon" still, love the idea of It being a Doomsday device or maybe being fragmented into 21 pieces one for each son of the Emperor, like a c'tan

[@davidbarko7004]

Nothing. They were the first two sacrifices to power the Golden Throne. Magnus was going to be the third. That was why Dorn asked Malcador to make him forget, because the truth was too horrific to bear.

[@mr.raider7865]

Sounds cool actually

[@SafetyBriefer]

Not bad.

[@jagnestormskull3178]

Not bad. Grimdark without being too grimderp.

[@MWH12085]

My theory is at least one of them was/is a Psyker. At least on par with Magnus

[@MrPiccolop]

Not bad, not bad (rubs chin)

[@levrapport2033]

A theory I've heard (though it's old so possibly outdated) is that both II and XI fell during the Rang'Dan xenocide, or some other conflict. What pissed the Big E off (to the despair of the other primarchs) was that His "perfect sons" failed: not failed to conquer their homeworlds in their youth and with no support (see Angron and technically Mortarian), but failed Him after He had found and elevated them to true demigods; even with a full legion of astartes and the might of the Imperium at their back, they simply lost. In those early days, the Emperor felt that He could not show any weakness, so He had the lost legions removed from all records and had their past accomplishments pinned to more successful primarchs. That's why the primarchs who knew them are saddened by their memory, or even angry (like Horus) that his otherwise successful brothers were erased so as not to tarnish the Imperium's image of invincibility.

[@ericmiller254]

There is a story about Dorn where he regains his memories of them Short Story - The Chamber at the End of Memory It doesn't imply that sort of brutal decision making. But maybe *shrug*. Dorn seems to totally accept what E did Didn't 100% close the door on it.

[@alexanderm8880]

My headcannon is that one was raised on a planet that revered some hidden exodites and as such was found to be too xeno friendly and escaped into the unknown regions on a Craftworld and passed from communication with the galaxy. The other took shortcuts in the Astartes creation process to create vast numbers which caused the majority of his legion to be taken over by the Rangdan. The second would explain how the Space Wolves had experience killing Astartes and yet it would still be considered unthinkable--they killed Xeno controlled Astartes.

[@jean-luclorusso]

Yep this.

[@psychedashell]

Don't people debate that experience killing marines as "The Night of the Wolf"? Going to war with Angron's boys?

[@alexanderm8880]

@@psychedashell It definitely helped, lol. At the same time the lore's pretty adamant that the Wolves helped "redact" the two legions so it's hard to imagine it was just Russ tanking two Primarchs

[@Leptospirosi]

@@alexanderm8880 I don't think the "shortcut" idea would work: Corax would never been approved trying to fast grow new legionary after the Istvan Massacre if such a precedent existed and furthermore we know both legions were fully functional after the two primarch went lost as they were intermixed with The Fists and the Ultramarine without much issues. Something bad happened to the Primarch, but I would exclude chaos taint or any gruesome genetic flaw in the leftover legions as the aforementioned mixing wouldn't had allowed. As for the implication Russ was involved in the wiping of the Legion it's not as "Adamant" as you think: we know one of the two genetic line went bad from Sanguinius, but, if you read the passage Russ states it "would not be the first time the wolf take on other legions", but we already know it happened several time, on the World Eaters, on the Dark Angels and on the Thousand Sons during the scruff in the Library while campaigning together, so implying Russ was directly involved remain pure speculation.

[@alexanderm8880]

@@Leptospirosi My idea was more that he skipped some stages like not indoctrinating as much and skipping some organs more than manipulating the geneseed itself, and maybe taking recruits from older populations so the transformation was faster but less effective in terms of muscle mass etc

[@alexluelo]

I never liked how GW handles the missing primarchs or these two. They treat it as a black box, a writing tool they can fall back on and they just starve us of content.

[@MWH12085]

Yeah, they could've at least given us an identity of the two and some very basic info on the Legions (out of universe, in-universe they could still have little to no records). And that they seemingly vanished with little to no trace.

[@jacobriley2874]

"Starve us of content" as if 40k isnt one of the deepest and richest of all fictional universes on record, which is constantly being added to. The mystery box is a legitimate writing tool that hooks readers and or audiences. 40k has a bunch of em, along with tons and tons of other content, and they like to shine a tiny bit of light on them at a time to keep people interested. Its artfully done.

[@user-yf4jx6te2b]

I have always understood the forgotten primarchs to be blank slates so that players like you and I could create a custom chapter with a lineage deriving from the forgotten. One primarch serves for loyalist chapters, and one for the traitor legions. I would have to disagree with the "starve us of content". GW does foolish things and money grabs, but you cannot say, given the incredibly rich and complex nature of the lore in 40k, that GW has done anything but overstuff the lore with detail and content. Also, mystery is interesting to a lot of people.

[@DavieTait]

What if the "Rangdan" were one of the legions that turned against the Emperor , using Xenotech against the Imperium that left the only Legion able to destroy them as the 1st...

[@SafetyBriefer]

I like the theory that one Primarch fell in battle during the Ragdan Genocides. The other was purged for failing to come to the other Primarch's aide. A primarch dying would be an affront to the perception of the Great Crusade. But why not give fans the story of the II and XI? There's mystery aplenty out there.

[@Leptospirosi]

There is a strong possibility that something happened during the Rangdan wars as we have sketchy reference to "unknown" legions being there, and yet, they'd have to be completely wiped out there, as we know most of the Legionaries were then melted, at one time, into Dorns ans Gullys legions. Why not into the Dark Angels which were present and suffered horrendous losses fighting alongside them, to the point of getting crippled as a fighting force for decades? Why the II Legion was not melted with the first? I'm assuming the II Legion as Fulgrim describes the II Legion primarch as alive and well, so I guess the one gone "bad" was the Primarch of the XI. I dont think the two unknown legions were lost in the Rangdan war, which also would not explain why their names and history had to be redacted.

[@barlotardy]

They beat big E to godhood, obviously. **Cough**Malal and Sigmar**Cough**

[@ericmiller254]

I think GW retconned sigmar out bro Malal...nah

[@christopheraaron1255]

Close... the original list had them as Sigmar and Belakor.

[@hydradominatus3641]

My head lore is they broke off from The Imperium to try and save a human race that didn't comply. They have access to fully functional STC and are laying low in a pocket dimension like The webway.

[@DonPetexX]

Like the interex empire?

[@DukeGyug]

I go with murder suicide. Not sure if it fits with the small bits of lore we know. But one is ordered by big E to kill the other for some slight, and after slaying his brother, his mind breaks, he is almost taken by chaos and can not take the realization of not only the lies told to him, or the darkness of the truth. Rather than serve either. He returns to his flagship and crashes it into the planet surface at his legion's staging area, ending the invasion and killing off a substantial percentage of his own sons.

[@kriegsmanalpharius]

Hydra Dominatus brother

[@-Gilver]

The biggest theory I've always entertained is a genetic instability or issue that was exploited by a Xenos race during the great crusade Specifically sometime around the Rangdan Xenocides

[@argentumvulpus6060]

I cant remember if there were actual hints one or both were involved in the rangdan xenocides and fell to their psychic powers which in turn let them be mind controlled to fight the imperium, or if that was just a fan theory talked about online... but I like it

[@TheMasterPandaBear]

Thats what I like to think, that at least one of them had to basically be "Euthanized" either by then falling to extreme mutation or being mind controlled with maybe some lucid moments, if its the first one ot would make sense that the emperor choose to purge him from history, as his fall wouldn't be because of chaos but his own failure.

[@ericmiller254]

They've X'd that one out. Cawl says they're fine and the geneseed can be used.

[@TheMasterPandaBear]

Yeah, the legion is fine but maybe it only happened to the Primach

[@-Gilver]

@@TheMasterPandaBear legions tend to be extremely influenced by their Primarchs in some degree so that's possible

[@fredesca8648]

One of them was Sigmar Heldenhammer, Primarch of the Stormcast Eternals.

[@i-kneel-for-no-man3814]

That’s actually damn good of an theory. I really like that one.

[@fredesca8648]

@@i-kneel-for-no-man3814 it's an old theory.

[@giocrypt5148]

Make sense as Zigmar is basically a barbarian king, which is an aspect (culture) not represented in 40K

[@i-kneel-for-no-man3814]

@@giocrypt5148 And he’s called the man god. And what did big E hate the most?

[@Leptospirosi]

But we know they were both found at some point: the Primarch of the II very early as Fulgrim remember meeting him, the XI Legion primarch, later but before Corax and the revelation/finding of Alpharius/Omegon

[@rhysjones6830]

II: Xeno specialists (maybe sympathisers) Played a part on the wrong side of the Rangdan Xenocides. XI: Pariah/Null Legion (Void specialists as nobody wanted to hang out with them) Malcador had them fake their destruction so they could be a secret weapon against chaos, Leman being the only one who knows this is currently looking for his lost brother in the Warp...

[@jkee9760]

I always imagined one of them, specifically who ever is the "lost" had a blank gene in them that made them unsettling and so the emperor made them leave and became lost. Idk something along that. Inb4 "muh sisters of silence" Like the emperor sent them deep into the warp, as a chapter full of pariah gene masters and his suspicion about the knowledge of the warp made him say they are lost

[@redaerf2b414]

Yeah, how else emperor got so many silent sisters, since they are supposed to be very rare. I think He experimented with creating blank people, including even astartes and a primarch.

[@whythelongface64]

Maybe even the emperor couldn't take their BS soul hacks

[@HammarPwnsYourFace]

I totally agree with this one. Blanks would be insane as a primarch much less 70,000 smaller versions...

[@eotwkdp]

@@HammarPwnsYourFace there’s a fanfic about that

[@eotwkdp]

There’s a fanfic where he had a son who was blank but was killed by a surviving old one. The emperor greeted his blank son by hugging him. He joined his father crusade But then rangdan wars began The rangdan were being led by a surviving old one The emperor and the old one fought in each wounding each other greatly The blank son Knowing that their father is the main key to man kinda dream sacrifice him self and 80% of sons. But before sacrifice He used the very same machines that made the necrons Like the silent king He got the good shit and his powers were amplified to Alpha blank status He also turned his sons into necron space marines

[@bernardotorres5274]

Yours actually sound pretty cool! My theories are the following: 1) The Gene Master When we look at the Primarchs we see them not only as powerful beings but they are also representations of the Emperor and its vast powers, for example: - Sanguinius/Konrad: are the emperors wyes that allow him to see the many dark or bright futures he could create - Reboute: His organization and tactical genius - Russ: His ferocity and stubbornness - Vulcan: His Linda and eternal regeneration/rebirth - Horus: His charisma and leadership - Dorn: His dedication and ability to warmer off the warp - Magnus: His immense psych power and hunger for knowledge - Etc. But we always see missing a key characteristic from the Emperor and that one power that allowed the creation of his Emperium, and that is his ability to manipulate genetic material. I do believe that either 2 or 11 represented this characteristic and that is why I call it the Gene Master. This Gene Master story is that he landed on a rich natural world in which he was able to breed near perfect creatures thanks to his talent. When he was found by a colony of humans and was given the proper technology his talent was finally able to manifest, and he began as a doctor curing many disease and driven many bacterias and viruses extinct in his homeworld, making its inhabitants the healthiest humans in the Universe. Soon he began to manipulate genes his very own and to distribute it with his people and allowed his population become essentially perfect, and he was even capable of creating his own version of Custodes (which one would believe it if they check their genetic material and find out that if match 99% of the Emperor's own Custodes). However he soon found out that his Genes were flawed due to the warp, and it develop into forming mutations. His people began to mutate and so did he, he tried in bane to stable his genes, to find a cure but it was futile, soon the entire planet looked like a Chaos infested planet and his people to look like chaos spawns. When the Emperor arrived to meet him, he saw the horror of this and at first thought that the planet was Chaos Infested. When he went to confront his son what he found out was nothing but a malformed amalgamation that spread around the planet like a cancer, at the center lied a broken man, who beg his father to kill him. The Emperor was for the first time in his life horrified beyond belief, and he forced to do so. He ordered the planet to be purged and that no one could know of this, for this could create fear on a scale of disastrous consequences. This could be the reason why both Magnus and Sanguinius fear for their legions, because they sound the pain and suffering they could undergo. Not to mention that the Emperor would feel a great shame if it was discovered that one of his children was so flawed it lead to its death. However Malcador and some tech priest found use on the Gene Masters DNA, which they found out that one mixed with another Primarch DNA the subject would not mutate so rapidly or so horribly and thus created some of this hybrid legions that introduced as normal Marines and they waited and watch for the outcome. Said outcome came in the form of the Carcharodon, Black Dragon and so on. 2) The Damned Son: This Primarch did not survived the kidnapping of the Dark Gods and he essentially desintegrated within the warp, becoming part of it. However he was not lost or purge for all eternity in fact he became his very entity in the Warp but did not ascend as a God or an extension of Chaos. He became pure energy that travels around the Warp and at times gets the strength enough to manifest into the material world. However he manifestantes not as a Hod or a human form, but as a Legion. The Legion of the Damned ( we have seen this Legion manifest from time to time to aid the Imperium, but do so at random they even appeared during the siege of terrarium fending off daemons). This entity would also be the o e responsible to collect the souls of loyal Astartes and give them the rest many deserve, but those with vengeance in their hearts he allows them to join his legion and not only fight along his tethered and the Imperium but also to claim vengeance and punish the enemy. Essentially this Primarch could be the very section of the Warp that all loyal human souls go to. Perhaps he is also the one helping to keep the Emperor alive by helping him fend off chaos from their section of the warp as much as possible.

[@Masterfulmodernman]

Whoa, never heard either of these theories, both are badass. Good thinkin there.

[@dr.rotwang]

In universe I always figured it had to be something directly related to a failing of the emperor. I think that it has to be something that could be directly tied to the emperor that they don't want getting out. Like an unstable primarch who's genetics were bad and went completely insane over time. Or one where unstable mutation, not warp chaos tzeentch mutation mind you but the emperor and his science dun borked and created a mutant primarch. Can't have two of the emperor's sons be a raving lunatic or giant monster because the Big E screwed up. So the imperium does what they always do and killed those that couldn't be saved, hid those that could, and covered it up. It goes a long way to explain most if not all the teases we've gotten over the years. Hours' lamentations, Russ' regrets, Sanguinius' fears about the flaw, the offer of a new legion to magnus, the night haunter's visions/fears, etc. It would also explain why the other primarchs feel such loss, remember them fondly, and believe their demise to not be any way their fault. Just my 2 cents.

[@Hotsoe]

My theory is that they mutated to a degree, that couldn‘t be tolerated. You can take that from the conversation between horus and sanguinius. But frankly, we should interview one of the traitor primarchs.

[@wetzel4806]

Same, also explains why so many Ultramarines successors have odd mutations, they're decended from the lost.

[@MWH12085]

I don't know, Cawl stated, in his examination, that there was nothing wrong with the geneseed of 2 or 11. I honestly don't think the Primarchs have the full story......because GW sure as shit doesn't.

[@garrettflaherty5440]

I think it was saving somewhere that even the traitor primarch won't talk about it

[@ericmiller254]

While it's vaguely implied. Leaves a lot of room in there for him to be scared of getting wiped out for any reason.

[@MWH12085]

@@ericmiller254 that's what I thought. Just getting erased for ANY reason rather than a specific reason.

[@TheMasterPandaBear]

I like to think that one of them committed suicide, maybe he discovered something about the Emperor he wasn't supposed to know, maybe he faced an eldritch horror from the ghoul stars and could not handle it. Maybe he didn't share the emperor vision and it was the only way out without putting his legion in danger. A Primach taking his own life, unspeakable.

[@MrPiccolop]

That's something

[@eoinfrompartsunknown]

Never heard this theory before and I really like it.

[@ghoul4748]

>TFW too intelligent to live in the 40k universe.

[@ianharrison5758]

That really would explain why Horus was so mad they were to be forgotten. If one of my brothers killed himself my family decided to edit him out of pictures I’d be pissed too

[@High_Kahl_Ray]

A fall to chaos would make sense when you consider that the Emperor was trying to keep all knowledge of Chaos an absolute secret, especially if only the primarchs fell. Say spawndom even?

[@jacked4121]

Would also show wolf boys hatred towards the librarium in that he had to witness similar “magic” and had to put the 2 legions down. He’s known as the emperors “executioner” after all

[@redaerf2b414]

If they were corrupted, chaos gods wouldnt let them just die, unless of course emperor himself hadnt killed them. Also, their fate is known to brothers, so true dangers of warp would have been known also.

[@Leptospirosi]

As the Chaos realm and their denizen were a strictly kept secret by Big E and Malky, I guess even them and part of their Legion dying fighting a full Chaos invasion would be enough to be expunged, but still respected by the other Brothers who did not know the detail of the mess. He'd they fell into chaos, I guess they would be as despised as the Heretic Brothers that followed. I also don't think, if part of the Legion had fallen into chaos, the leftover would be intermixed with existing ones. Remember Horus was completely oblivious of Chaos when the contacted the Interex quite late in the Crusade.

[@joshw9277]

Or falling into the Eye

[@adrienwatson2179]

@@jacked4121 Thr Rangdan could mind control. Leman may be the executioner But Lion El Johnson was the "Exterimator" In all likelihood one of them fell to the Rangdan and the DA/SW had to go and sort them out. My guess is the 2nd Legion and their Primarch, ad it was said by Fulgrim that he was so powerful that one Primarch wouldnt be enough. He also apparently had absolutly ZERO sense of humor (The 2nd Legion Primarch)

[@Jpipooly]

I've come to head-canon that one of them sought to forge their own, competing Imperium. This would add to the gravity of Guilliman founding the Imperium Secundus and add further weight to the Emperor's treatment of the Word Bearers. Not only did Lorgar's faith give might to the hidden powers of the Warp, but it could have split the Imperium in and of itself if left to fester.

[@michaelhowell2326]

I think there is more to the UM absorbing the two lost Primarch's Legions. On several UM models the XIII is represented as XI and II.

[@MWH12085]

Well 2+11=13

[@michaelhowell2326]

@@MWH12085 No. Shit.

[@kelman727]

Nothing more than a fan theory; ADB shot it down, since it was a throwaway comment in one of his books started it.

[@MWH12085]

@@michaelhowell2326 glad to see somebody got it. Otherwise, I'd feel like my efforts were all on vain.

[@chrisbennett6236]

Russ talking about Astartes vs. Astartes at the very least includes when he and his Wolves moved against Angron and his World Eaters. That was a great book by the way. I love how easily Russ maneuvered his Wolves in between Angron and his sons. Effectively cutting him off.

[@silversurfer8818]

Dan Abnett said in an interview, that if the high lords of GW told him to write about them, he would be elated to do it. But to keep them in the shadows because of some tabletop game i care nothing for, i assume most doesn't. Would be the wrong reasons, i care more about the two lost Primarchs than finishing the siege of terra.

[@daveeol1987]

But it would never live up to the hype and be a let down best kept redacted

[@ericmiller254]

@@daveeol1987 What hype? we know nothing lol if they have a good idea for another legion, why not?

[@squishymusic9723]

I think he, or another writer, said that they the concepts were in place and they had planned/already started to write them. But the higherups changed their mind because they believed that it would be ultimately disappointing since the whole point of the lost legions was the mystery.

[@MWH12085]

@@squishymusic9723 No matter what, you're gonna disappoint someone. But I believe it can't be any worse than the jumbled mess it is now. Plus, GW doesn't seem to appreciate fan creativity anymore so why keep this up when you could create ANOTHER starter set to sell for $800 dollars?

[@squishymusic9723]

@@MWH12085 Well if they wanted to make 2 more Primarch models, even non canon ones I wouldn't complain 🤣 Honestly I don't think it is a jumbled mess, they havent been overly heavy handed with the mystery its just the general confusion over what was so unforgivable - which would probably be a disappointment to find out

[@DocMadfox]

My headcanon is one of them was a technological genius, designed by the Emperor to help him build the webway. However something went wrong with the webway that resulted in that one's death or betrayal and helped cement the Emperor's idea that the Primarchs weren't ready to know about the webway. The other was then ordered to destroy his brother's Legion with the claim of them going rogue, but refused, at which point Russ and The Lion (who has in the past implied he took part in killing the Lost Legions, but like Magnus punching out one of Leman's hearts, no one remembers that) were sent to destroy the Primarchs and their Legions, after which the Legionaries who surrenders were absorbed into the Ultramarines at Malacador's behest. Optionally: Later the Brother that was a tech genius' sons were split off from the Ultramarines, forming the Blood Ravens.

[@jagnestormskull3178]

I had a similar idea about one being a tech genius! Maybe he tried to build an AI (not something inherently corrupting or even CORRUPTED (see the story "Man of Iron"), but forbidden due to cultural scarring) and the Emperor ordered the Primarch's Legion's memories to be erased.

[@KantFromEC]

I wouldn't mind finding out what happened to one of them. Keep one mysterious but reveal that one never accepted its nature, never conquered its world and lived a humble life when the Big E found him. Destroying him to hide the failure of a Primarch not fulfilling his duty and the Emperors failure to mobilise him. You could have a story about akin to 'The Last Church' but between the Emperor and his wayward son.

[@richardhowells5804]

Maybe something happened to them on Molok, when the Emperor went back to the stable warp gate. That would add another reason to why the Emperor erased the memories of Horus and the other known Primarchs that were with him.

[@sidiouswargaming3971]

In my mind, one was lost early in the crusade, during the largest campaign after the Hersey with a massive xeno empire where he failed so horribly, he was removed from history, being a disgrace and the second was a very small but elite legion of anti pyskers/ chaos that was ultimately destroyed in one way or another . My custom legion follows the later, being blanks that fought during the Hersey but after losing their primarch as well as most of the legion itself, the primarches sister asked the emperor to delete them from history before going on a permanent penndence crusade, never to be seen again.

[@Tellemicus]

I think you're only half right. One of them definitely fell and was twisted by Chaos. And that was how and why Leman became known as the Executioner. But I think the other was completely ANNIHILATED to the last man by the Rangda xenos. After all, how else could they have gotten the reputation for destroying whole legions than if they had already done it?

[@overgrowndwarf1628]

It's the "Rangdan," but it's very telling that you used "Rangda," who is a Queen among Demons in Balinese Mythology.

[@Tellemicus]

@@overgrowndwarf1628 Yeah, telling in that I've only recently gotten into the lore

[@overgrowndwarf1628]

@@Tellemicus I wonder if it was intentional, and the Rangdan have a demonic connection.

[@housetoocrowded7825]

The 2nd Primarch was referenced in the Fulgrim Primarch book. The burial place of both Primarchs is referenced as being in the Imperial Palace. Dorn found it when fortification of the Imperial Palace. The Chamber at Memories end

[@gentlemanviking2644]

Before we had the rise of Primaris I imagined that at least one of those two Primarchs were lost in a massive warp storm, but they were bought forth to the 41st millennium by the god emperor to defend Terra at the 11th hour, surrounded by chaos and xenos.

[@headquarters447]

I like the idea that one of them was wiped out tragically as they battled some big threat, and the other in their grief turned against the Emperor who "carelessly" sacrificed his brother. Russ was sent to put the rebellion down, the Ultramarine absorbed the loyalists among them, Russ is sad because he sympathizes with his slain brother. The Emperor erased them. Because the Imperium can't have the public knowing that a.) the Emperors legions aren't invincible, and b.) they aren't perfectly loyal.

[@neogeta7336]

My headcanon was the lost two were changed by Tzeentch to be female, exiled to the rim by the Emperor and declared lost.

[@MWH12085]

My Head cannon is one of them is female (Primarch #2). Since the Primarchs are based off various gods of antiquity, She's based off Freya. Among the many hats she wore, she was the Goddess of the dead as well as The Queen of The Valkyrie. So rather than exiled, she was put in charge of a special assignment (Legion of The Damned and The Living Saints).

[@ianharrison5758]

This is more fan fiction than fan theory but it would be dope to see become cannon. It’s based on the Theory that primarchs souls are powerful warp entities(that’s important for one of the lost primarchs) I like the idea that the emperor is playing a much much longer game plan than what we ever imagined. He knew, that in order to be able to combat the influence of chaos on humanity, he would need to be a god. The imperial truth was designed to give chaos the illusion of his empire falling into ruin. Instead, he turned the imperium into what it is now in order to 1. Guarantee the most fervent and extreme worship imaginable, to equal the fuel the chaos gods get from humanity. 2. Make the chaos gods think this ISNT what he wants. To the chaos gods, the galaxy is already theres, that’s why they don’t jump the emperor in the warp. He’s more of a nuisance than a threat, so they think, he’s only one god after all. The lost primarchs were not expunged due to failure, they were erased to keep them utterly secret. Even changing the names of them in the minds of the primarchs who remember to ensure they are never revealed, the nature of their missions too vital to risk even the tiniest chance the ruinous powers learn of them, or in the case that they do, that what they learn is false. One of the lost primarch was given the mission of building an army within the void beyond the Milky Way, an army that was allowed to use any tech from the dark age, except AI, to build a force strong enough to be able to destroy both the imperium and chaos forces on near any scale should the need arise. The other primarch is Malal, or Malice. The emperor placed Malice within the body of a primarch before the emotion that fed him gained sentience in the warp, stopping malice from forming the way a chaos god would , and instead siphoning that power into a living being who was loyal to the emperor. This was not hatred given life, rather, is a human being powered by hatred the same way the emperor is by worship. He is Deep in the dungeons of terra, letting the hatred of trillions feed his power, hiding his true strength from the Chaos gods, and waiting for the endgame to begin. The emperor knew he could never 1v4 the chaos gods and win while fighting in both real space and the warp alone. He created Malice to be the protector of Humanity in real space, while he ascends fully into a warp god. The terminus decree is to Free Malice from the Palace dungeons and Kill the emperor. The explosion of the golden throne, combined with him truly ascending would create a warp rift similar to the eye of terror, but under the emperors control. He would claim it as his own territory within the warp, taking his place as a warp god, while the now material god Malice would defend the Imperium against any real space attacks. While the emperor engages part two of the plan. Were humanity to be destroyed by the hand of chaos, it would never recover, but if it fell by its own hand, it could. The emperor would then order his Void army to exterminate the majority of the human race, hence why they needed access to dark age tech. This would weaken the Chaos gods in a way they could never truly recover from. By ascending into a god, all of those who worship the emperor automatically become similar to followers of the chaos gods. They do not need to make a deal with you to claim your soul if you worship them as a god already, same with the emperor, so the souls of the purged humanity that worships him would empower him the regardless of the fact that he ordered their death. This would give Humanity utter dominance of both the Warp, with the emperor winning the great game, and in real space, where Malice protects humanity from any and all threats. This would allow humanity to ascend as a psychic race while no longer needing the webway at all, ensuring humanity safety from chaos and all Xenos accept the Tyranids. Instead of wasting what’s left of humanity warring with the Tau, Eldar and Necrons, the new imperium creates an alliance with them, to ensure the end of the Tyranids above all else. Maybe the new imperium goes to war with Necrons and Eldar after they beat back the hive fleets, or maybe the galaxy finally enters an era of peace that rivals the years before the war in heaven.

[@CoolCraftCool]

We are always told that the Primarchs are aspects of the emperor so what are we missing. We have the warrior, psionics, tactical planners, leaders, statesman, secretive and deceptive, forgers and builders. Where the hell is the geneticist where is the biology buff? It would make sense if we had a Primarch who did a Fabius and wants to enhance all of mankind?

[@iamcaesar6741]

I like the idea of the 2 Primarchs sent on a mission to establish a fall back human colony on the other side of the gallery. In relationship to the Asimov novel Foundation Series Novels. Their mission is to continue to fight forward until the human colony is ready at coordinates exactly the opposite of the galaxy

[@Fissiccisst1]

Man, its really interesting to thing about. What gets me every time is: Why expunge their records? If the Horus Heresy wasn't enough, what possibly could they have done? Also the complication that the other primarchs regard them not with hatred, but almost sadness and regret. Its almost like whatever happened was less confrontational, but more emotionally based. Like something shameful happened, as opposed to being destroyed by something. And they had to be strong, or else other primarchs wouldn't be pining for their presence during hard times. If they were just weak, or useless, they wouldn't be regarded with such fondness. If they died fighting, they would be remembered as heroes, to be used as beacons of hope for the people, not thrown away to be forgotten. The fact they got legions at all means their time away didn't completely trash them, especially considering even Angron got a spot despite everything. So it couldn't be anything overtly obvious, else they wouldn't have gotten to legion strength under their primarchs command. I imagine if the Horus Heresey was smaller, they also would have been purged from history, but the conflict was too large to sweep under the rug. So instead they are left remembered, as a beacon to unite humanity against a common foe. I think its less that its any better or worse that the Heresey, its simply the timing and the scale that allowed them to be purged instead of used as a rallying cry. Imma steal other people ideas a little and make this guess: 11th Legion found the absolute first trace of the tyranids, who had sent exploratory teams to multiple galaxies looking for food. They got genestealered, or something, from the top to bottom, first subtly corrupting the 11th primarch, who then propagated the corruption to the entire legion. After the corruption was discovered the 2nd legion was sent to wipe them out. During the resulting war, the 11th legion loses, but not before a fight between the two Primarchs have some kind of fight. The 11th primarch, still of sound mind, but unable to control his action asks his brother to purge him and his legion. Better to die at the hands of a brother, than to continue living this way. During the fight, the 2nd primarch, cursing his brothers fate loses focus and takes a blow to the brain and permanently loses all his memory and motor function, not who he is, or ever was. Alive only physically. Russ arrives, too late, eradicating most of the 11th and seeing the aftermath of the Primarch fight. His brother, still begging for death is executed by Russ, who does it with equal parts punishment, and mercy. While the remains of the 11th legion escape to dark space, heralds that the galaxy is ripe for the harvest. The tyranids were already on their way before the beacon, but the beacon spurred them even faster. The emperor, fearing having to explain the primarchs are not as infallible as is to be believed to the Imperium at large, wipes the conflict, and the legions from records. With only their brothers to mourn them; The 11th, the Purged, for having lost, not to a foe he could fight, but effectively a plague. Knowing he did not willingly fight his brother. And the 2nd, the Forgotten, who to this day, resides in a room in the palace, mute, immobile, with his brothers waiting for the day his mind will return, if it ever will. Side Note: Doesn't have to be tyranids though. Insert any generic space super virus/disease/fungus that could kill/corrupt Spess Muhrines from some long lost planet (that was surely nuked from orbit following this incident)

[@kylemoss7941]

I only vaguely remember 1 of the lost, the mad king. Brought to a world resembling medieval times, where gunpowder was still new, the mad king was found. Barbaric and tribal, he was wracked with potent portents of the future, and once brought in, could see what the empire of man was to become. He mad his way to a place where his father, the emperor, once entered the warp to barter the chaos gods for power, in an attempt to make his own bargain. This was his end.

[@michasalamon8315]

I bet that one of them, most likely the 2th since we know a little about him, have been some sort necron ally or was using their technology, went full Doctor Frankenstein, and started to make sore horrible shit with 11th's marines, since they were getting very easly mutated, maybe at first trying to heal the 11th's mutations, but went insane, turned them into literal monsters, and send them rampant across the galaxy, what caused Emps to send Leman and Space Wolves to destroy the 2th legion, and put the 11th out of his mercy, and take the "loyalist" survivors to join Ultramarines and Imperial Fists. I was led to this by many hints left in the novels. Fulgrim and Emperor children's marines mentioned two times that the 2th primarch was a bit of an asshole, and his legion was sent to what is today a Necron dynasty territory. While the part about 11th legion being heavily mutated and therefore exterminated comes from Sangiunius telling Horus that he kills the marines that fall to the thirst and black rage because it WOULD BE NOT, the first time Emperor killed an entire legion because of genetic flaws. The 11th legion can also be the original legion of the present day heavely mutated chapters like Black Dragons that even in early stages of mutations were developing things like horns, claws, tusks, tails, fangs, talons, or even stuff like breathing fire and growing lizard/beast like body structures. The idea that the 2th primarch and his legion purposefuly mutated/used the 11th primarch and his legion comes from the fact that they are called Lost and Forgotten, meaning that one was lost to them, meaning they failed somehow, and the forgotten, most likely means that they did something very shameful what caused them to be eradicated from memory, and in my opinion the only shit bad enought to get this sort of treatment is turnign an entire, or at least majority of space marine legion, into a horde of steroid filled monsters like Wulfen, Red Thirst mutated marines.

[@codyblazejackson3077]

One Lost to the Rang'Dan, one Purged for slaying the one that is Lost. Russ and his Wolves executed the Primarch and Legion of the Purged.

[@Bruva_Ayamhyt]

Source?

[@jodi1761]

@@Bruva_Ayamhyt For the first statement: Inferno. The rest is just made up.

[@chrismorel8613]

Russ and curze most likely. In first heretic the deamon tells lorgar that's his fate in one of the myriad futures. So there's some hints of the two of them working together as the 'tidy up team"

[@Skygod104]

I too believe that both were involved in the Rangdan zenocides, but I believe that prior to the heresy, the Emperor led everyone to believe that his space marine legions were invincible. And then they encountered the Rangdan and they put paid to that fable. The Second and Eleventh legion Primarchs had to pay the price for the Emperor to save face. To preserve the myth that the Primarchs and their legions were invincible. What was left after Leman Russ cleaned up the mess was folded into the Ultramarines. I admit, it still leaves a lot of questions and while everyone loves a good mystery, the reason everyone loves a good mystery is that they love to try and solve it. I'm thinking this mystery of the Lost Primarchs will eventually have to have a solution put forth by GW. Yes, it does take away some of the player fiat with the solution, but it also opens up new ideas and new avenues for creativity by both GW and the players. Just my thoughts.

[@last2nkow]

my head cannon is that one brother fell to something worse than Chaos, Peace. imagine the heresy and damage to the Imperium if one of the Legions primarchs decided that they had simply conquered enough, turned their swords to Ploughshares and set about simply enriching the territories they had claimed, stalling the crusade by being satisfied with what they had done and refusing to take orders to go back into a war they wanted no part in. the Wolves would be absolutely the right Legion to send to deal with that. Leman russ and the Space wolves would have the honour and outlook that might best get through to them to turn them back to the war, and were reliable enough that they would be able to try and force them if they had to. i imagine Russ and the 2nd Primarch meeting and arguing and both being diametrically opposed. 2nd is noble, and good and cares for his brother and tries to get Leman to see things his way, but Russ simply cannot back down. they come to blows and 2nd and Russ fight. but 2nd makes the decision to stop the bloodshed and lets Russ make the call. he wont go back to war, and Russ cannot let him return to peace. So Russ Kills him and the legion of the 2nd primarch are slaughtered by their Brothers. only those who take up arms and agree to follow Guillemin are spared. thats my 2 pence, thanks for reading.

[@DaveCertifiedS]

Alright, here me out... we know that each of the primarchs were created slightly differently as each was intended to serve some various role. The Warp also does it's thing and so does wherever the primarch lived prior to being found. We also know that Easy E is all for trying to make the best out of a bad situation as with Morty and Angry Boy. However, we also know that E Honda will purge entire legions if they don't work for the larger goals any longer, please see the Thunder Cats... er Warriors... for details. We also know that E=MC2 has an image to maintain. So here's my theory: The Lost Boys get picked up. At first they show markers that indicate some kind of damage, perhaps on par with Angry Boy, E-Diddy wants to make it work so he straddles them with a legion and sends them off to spread the good word. While they are out there doing their thing, it becomes clear that there is something inherently broken about these primarchs. So Emma has them recalled to Terra and finds out that his creation process led to unforeseen complications due to whatever it was he wanted them to do. This isn't some warp shenanigans or bad childhood experiences, these eggs broke before they were shipped. That's a bad look, as the kids say, so everything has to be purged, they can't exist because the Empanada of Man can't be flawed. Of course, this sends shockwaves through the other primarchs , don't mess up, you and your legions can be erased.

[@The_Shoebill3D]

one of us is having a stroke reading this, and idk who

[@mr.raider7865]

I want to take a second to appreciate the amount of variable names you came up for the big ed, edd and eddy

[@DaveCertifiedS]

@@mr.raider7865 why thank you. Not sure why I stopped using Engelbert Humperdinck's name, but I try to keep it rolling. Also, kicking myself for not going with Angry Ron. And I remembered now, spell checking Warhammer names sucks.

[@mr.raider7865]

@@DaveCertifiedS alas haha

[@fearless204571]

Anything is possible at this point about the lost Primarchs. Whether they've been wiped from existence or they were sent out into the deep void to fight off a coming threat to mankind, it is kinda interesting when you think of it.

[@franklinjohnson4632]

My headcanon is that the 2nd primarch was popular amongst the others and was fighting in the ragdan crusade and discovered the 11th primarch who was a worshipper of chaos. He kills the 11th and then receives a vision from chaos of every universe that could be he tries to warn the emperor of some of the bad ones and how to make the good ones but the emperor knowing that he has discovered chaos and not wanting his other sons to discover chaos sends leman, Horus, and Curze to capture him. This ends badly as the 2nd is a great warrior and has the greatest purpose while the others don’t want to hurt the brother they love so much. He gets to the emperor tells him the about chaos the emperor explains that he must be exiled because he knows to much. Then he is forced to tell his other brothers that he killed the 11th because the 11th had been mind controlled by the ragdans. He would then be banished with only his veteran space marines accompanying him into the dark while the rest of his legion abs the 11th legion is absorbed into the ultramarines.

[@jonpaulevans31]

I like to think one of them landed on an Eldar Exodite world. Given his Primarch prowess, he was accepted. When Emp came to get him, he said, "Nah. These are my people." So, Emp fried him, gave his army to Roboute. It would have to be the 11th, as there was talk of the 2nd being at a meeting of Primarchs on Terra, (and being taciturn/quiet).

[@TK199999]

As much as I would like to know more about the lost and forgotten. I always felt GW could expand the lore about them without saying anything in one simple way. Start revealing what they did during the Great Crusade. Their victories and defeats. Which would leave the true nature of the lost and forgotten still up to fans. One important note, Malcador says out right he was tasked by the EoM to erase the reason for the fall and purging from all the Primarch's, along destroying all record of them. But revealed in that same conversation that Dorn and Guillemin saved the surviving members of the 2nd and 11th legions. By successfully convince the EoM that they did nothing wrong, that the sin was their Primarch and not themselves. We know that its possible that these survivors were made part of the Ultramarines and Imperial Fists. But that they had their gene seed switched out for their new legions. Something has happened before in the lore. In the end Malcador says the reason for purge and even erasing the remaining Primarch's memories. Was because the sin of the 2nd and 11th jeopardized everything the EoM was trying to do since he first started uniting Terra. Finally as to why knowledge of the traitor Primarch's remain in some fashion. Is because EoM was enthroned and Malcador was dead, so there was no one to order it or do it.

[@gandalf1379]

I like to think one of them was designed to be the diplomat. He was super chilled about xenos and was horrified by the stance of his father and mankind in general towards them. Maybe he is alive and just relaxes on some Eldar Craftworld or something.

[@ars273]

One was a powerful psyker, and fell to the temptations of chaos. The other was a null and took it upon himself to destroy his brother as their father was to far away to deal with him immediately. In the battle that ensued they destroyed each other. This was the Emporer's greatest regret, and so he hid the knowledge of this event to cover up his shame.

[@madmazogg7172]

This channel deserves far more attention and subscribers. Another fantastic entry. Cheers!

[@davidring681]

I think that one of the lost. Probably the purged was mind controlled along with some or most of his legion by some type of xenos. The forgotten might have gotten ambushed by this mind controlled legion. Thus we have a forgotten legion who just faded after being Virtually wiped out by combined xenos and mind controlled legion and primarch and the purged legion was the one that had to be put down along with the xenos. The “rang dang xenocide” or how ever you spell it is a good fit for this situation as it took 3 legions and the emperor to win that war and the records are lost or erased. Just a thought tho.

[@vortex_1336]

Not just 3 Legions and the Emperor. They were losing so badly the Emperor had to free the Void Dragon to use against them.

[@matthewsklut4886]

Maybe it's just as simple as: the 2 primarchs discovered Chaos WAAAAY too soon. So the Emporer just capped them and gave the other primarchs some bs story, which is why it never sat well with Horus.

[@housetoocrowded7825]

The fact that Dorn and Guliman recommended the Edict of Obliteration in order to remove the memory of both Primarchs says a lot. When Malcador let Dorn have a momentary reprieve in order to remember why they were removed from memory, Dorn realised that tha Heresy would already have been won by Horus and fa far worse fate would have awaited them. It’s clear that they both fell but it’s not explained why. It is also believed that they fell during or after the Rangdan campaign.

[@JB-mg8vm]

MAYBE it’s a case that if one primarch at a time really screws up (betrayal, mutates, loses a key campaign) it’s easier to redact / expunge them. Whereas 9 at a time - we’ll that’s just too much memory / IP to wipe out in one go

[@andrewmayocchi6659]

It makes certain sense to me that one of them was lost, with his Legion, in the warp and still has not returned. The Astartes that were not with him had their memories altered and were absorbed into the Ultramarines. The second was likely like Magnus yet a little ahead of his time in his corruption and Indulgence in Sorcery hence the need to purge him and his Legion. I heard somewhere that there is a Legion in Storage on Earth which could be used… yet it is considered an unthinkable option. Perhaps these are his gene children. Available… yet unthinkable.

[@HammarPwnsYourFace]

I like this theory addition -HydraDominatus

[@gadrielvanorion9872]

things i always thought could be with the primarchs we dont have with the19 we know 1. a primarch was raised as a civilian on a world that doesnt know war, and that primarch never was interested in the war and thus useless to the emperor ( or the emperor took mercy after a bit of time using him, and said. OKAY you can be free, i erase you, bb 2 a primarch in the emperors face tells him to get fucked, and or attack him then flees or dies by leman 3 a blank type primarch as a direct counter to magnus, designed to fuck the warp up this primarch got cut cuz he was dissabeling the warp so hard when he was grown up, he could no longer warp travel witthout the emperor, and even then he would weaken the emperor himself cuz primarch blank > normal blank 4 a primarch who was just straight up an asshole.... attacking his brothers, trying to conquer worlds that have already surrendered to his brothers 5 a primarch who defied the emperor and all his brothers on a specific code of honor, where other primarchs follow the emperor, this one says, i wont stand for this crap this lead to him getting the axe 6 a primarch who just fled away from the emperor as soon as he could abandoning the crusade 7 2 primarchs who just fking hate each other ( maybe 2 from above ) and during the rangdan xenocide there was a massiv civil war astartes vs astartes battle where 1 killed the other or majorly injured him, or made him flee out of the galaxy, prompting russ to finish the asylant one. 8 primarch who mutated... like.. not like sanguinius, we talking actual mutation 9 primarch attempting to rly take over the emperium as he sees the emperor as flawed / didnt like the emperors treatment of somebody such as angron perhaps 10 a primarch whos geneflaw was as intense as magnuses fleshchange, and this primarch got his legion culled, against him protesting whatever happened then happened. 11 a primarch actually taking a bullet for the emperor / or taking a bullet for some random civilian lowkey would love a lost primarch to maybe be in some sort of stasis in the throne room somewhere, and the emperor keeps him around should there be no other solution. and that primarch like guilliman was healing up perhaps the rangdan fucked his mind so hard, the emperor shelves him until he had the time to fix him up that would make sense too. then in the 10k years he used some of his spare power to heal that primarch slowly

[@gwilym1991]

So I recently heard a fan theory that to make the Primarchs the Emperor found 20 warp gods, and used them to make the Primarchs. Hence why they are the way they are as opposed to making 20 Guillimans or Dorns. Which is why there's a flash of energy when one dies, why only one Fulgrim clone worked (the entity went back in) and things like thr Sanguinor. If the lost Primarchs learned this, that would be a) a good reason to erase them but also b) why the big E never explained the Warp to his son, especially Magnus.

[@UncleCal]

One of the Primarchs emerged in the Large Magellanic Cloud following the scattering and created his own empire there. Uniting the long lost colonies who migrated there in humanities early expansion. An extra galactic effort was made to bring this area into the Imperium compliance via the Magellanic Expedition. Though was ultimately a failure due to the distance needed to support such an expedition - 163,000 light years, and the staunch resistance encountered. Thus the Primarch was struct from Imperial records and his fate is unknown.

[@NorthInfluenceGaming]

I often look to the Menducia Primarch Tarot for the best guess/estimation towards the nature of the Lost Primarchs, if only because it has some startlingly accurate observations of the other 18. To list the "worst" potential of each: II - The High Priest "Deeply psychic, the only one on a level with Magnus. However, his method is entirely different; whereas Magnus directs, the High Priest observes. Magnus uses the Warp, but the High Priest understands it. The High Priest is intuitively capable of predicting the motions and interactions of systems as a whole and guiding them holistically." "At worst, the ultimate tempter, conjuring unattainable, ever shifting but irresistible goals and twisting people's minds and desires without them even realizing what is happening, all for his own amusement." While the explanation doesn't explicitly say that there is a similar connection to the Warp that Magnus and the Emperor share, its does imply that there is some kind of connection. More of a spiritual one (?) like a middle-ground between Lorgar and Magnus. If that is the case, _and I ultimately understand this theory is based on shaky foundations_, then it might be that this Primarch was corrupted by the Warp in the same way that Emperor used the Warp/Chaos Gods to fuel his plans for expansion in the first place. Understanding them as means to an end but maybe not in the cut-and-dry way of the Emperor? X - Fortune "Does not appreciate being restricted, any may have a relaxed attitude to formal rules and regulations. However, he will have a keen sense of right and wrong. He understands that true order cannot be achieved through stasis and must allow some flexibility." "At worst, over-confident, too trusting, out of touch with people's real thoughts and out of control of events." Honestly, and I'm fine with the understanding that I'm wrong in this too, it sounds like further breeding ground for this Lost Primarch to have been interacting with the Warp/Chaos Gods in a capacity that ultimately led them to be considered a threat to the Imperial Truth. That being the case it would have be tamped out or maybe they even rose up in defiance of the Imperium believing that the Emperor had it all wrong? *TL;DR* Both of the Lost Primarchs had similar viewpoints to the Emperor in using the Warp or Chaos Gods as tools/"frenemies" to achieve their ends and the Emperor didn't gel with anyone else having that thinking.

[@wchamp170]

Here's my take. For whatever reasons those 2 and their legions were destroyed. Sanguinius actually kills Horus after Horus somehow hurt the emperor. Valdor executes Sanguinius , and sacrifices himself to save his legion from extermination. Sanguinius used his flaws to kill Horus. Chaos gods were constantly telling Horus he had to get Sanguinius on his side or he was screwed. Sanguinius was way too strong for Horus no matter how much chaos power they gave him and they knew it.

[@shorney11]

I do hope GW do a little more with the lost primarchs, made wind up the fanbase by briefly mentioning them without much details and maybe rule wise allow players to create their own primarchs in the same way a chapter master can be created.

[@bubbasbigblast8563]

It seems likely that at least one Legion went full "radical inquisitor," resolving to use the powers of Chaos to fight against the powers of Chaos. This way, there's a good reason they *have* to be erased from history: the Emperor would rightly fear whatever success arose from using Chaos against itself, and the traitor Legions themselves would not want to take the risk of their enemies finding weaknesses within the Ruinous Powers that could be exploited by studying such a Legion's efforts. You need only look at the Sisters of Battle and the Legion of the Damned to see how dangerous a Warp empowered Legion could truly be, even to the traitors.

[@saltyshackles5227]

My head canon; One of them saw the Emperors true form behind his glamour and discovered the Emperor is a artifical being from the DAOT called a Golden Man. The 2nd one was apart of a multi-xeno Empire and wasn't for the mass genocide of all xenos. EDIT: Golden Man with time travelling tech. My head canon is Big E awoken/activated as a last ditch effort to save humanity; but he woke up too late; during the Age of Strife of his original timeline. He realised he can't do shit, so went back in time and created a different timeline. This is why he was fighting the Dragon of Mars whilst trebuchets and arrows were being used back down on Earth.

[@1Smrdo]

My head canon is that they were corrupted by the Rangdan during that particular xenocide. They and their legions were subverted and used against the Emperor and the Imperium.

[@stephenknabe6423]

I speculate that there may be a possibility that they openly sympathized or even possibility tried to aide the alleged remnants of the Thunder Warriors, and had to be dealt with to keep that secret.

[@DanteMac26]

Mine has always been corruption. Either by xenos, or another human civilization. Maybe a Dark Age civilization that was hidden in the webway? Maybe one of them made their entire Legion read "Atlas Shrugged".

[@bulwyf2572]

I have always thought at least one of the missing primarchs and their legion was sent out of the galaxy to start preparing the nearest/best candidate galaxy for mankind's eventual growth into that galaxy. We know before the HH started that the Emperor had conquered most of this galaxy. It makes sense that the Emperor would then send one of his sons and that legion into another galaxy expecting the milky way galaxy to soon be his.

[@Knights_Oath]

I have always believed that the 2nd and his legion were wiped out in the Rangdan Xenocides hence The Lost. There was brief mention of them involving the campaign. I think the 11 was The Damned, I think he was corrupted, mutated, or went insane shortly before the Emperor found him. It was not apparent until he and legion joined the Great Crusade.

[@CaptainHelion]

some of my theories: 1) the second Primarch nearly or successfully caused (although most likely accidental) a Necron Tomb World to reactivate which was an extinction threat and against the ideals of the Great Crusade. (it is canon that the second visited the Monolith of Yuma [?] a suspected Necron construct and it was described that both did actions in contrast to the ideals of the Great Crusade. 2) one of them may have made something that the Emperor made think that he attracted Tyranids (the Imperial Palace had once a "telescope" allowing the observation of other Galaxies - and most likely also of the Tyranids) 3) Both were purged when people started asking questions about why the number of Primarchs is lower than that of the Legions. 4) Both Primarchs didn`t survived the scattering and the Emperor was forced why ever to manipulate everyone into thinking there were alive for at least a while. 5) One Legions seems to haven`t made it to bigger numbers than a few thousand and it is hinted that the science behind them didn't failed, meaning somebody had to intervene. The 11th primarch? That would be a huge affront to the Emperor and a possible danger for everybody around them (Like Black Rage and Red Thirst together but with the Marine able to use complex thoughts)

[@overgrowndwarf1628]

We know the two disappearances are unrelated. Dorn has stated that their tragedies were separate, but that these aberrations held warnings that went unheeded. I always thought it had to do with the Primarchs embodying different aspects of the Emperor. But there are a few emotions and concepts that aren't covered by "the angry one," "the beautiful one," "the psychic one," "the strong one," "the vain one," "the logical one," etc, etc... Notably: Fear. What if one went down to the Rangdan Crusade, but bungled it so badly because he couldn't function as a leader and a warrior? Maybe the Rangdan Xenocides would have never been as costly if he hadn't been involved. But despite this he was likeable and affable, and those who met him liked him, despite his cowardly ways. This would explain the anger from the few who we know definitely met him. This could have been Two, as he has been described as plain and taciturn, but that could have actually been shyness in the presence of his more "powerful" brothers. I think he's the "Forgotten." His Astartes were given to Guilliman, and he was hidden away, all records expunged - no trace of the perfect being that couldn't bear to fight. That leaves Eleven, who I believe may have been something else - the empty one. Devoid of a soul, of humanity, of joy, totally unfeeling - maybe he was a true monster. It is this that makes Sanguinius fearful that if the Red Thirst were ever to overtake his sons completely, they would be expunged. It was Eleven and his legion that Russ and the Wolves had been forced to execute, as their sociopathic psychosis was simply far too dangerous when backed by super-strength.

[@thepsykotik]

For me, I always thought one would be the devil to sanguinius’ angel. Mutated, but in a much less physically appealing way. I think one or more of the cursed founding chapters (black dragons?) could have been based on their gene seed and that the primarch is locked away in the imperial palace. The other I thought made the mistake of questioning the crusade and in particular the purging of all xenos. Probably because he grew up on a planet where one or more alien races lived in harmony with humans. Maybe they were forced to leave the galaxy?

[@chrismorel8613]

First time I saw the sigmarines and the whole AOS mythos, I did have the thought "Yeah okay, and your still sticking to the party line that sigmars not one of the missing primachs hmmm? Then I clicked they just lazy."

[@dracon501]

I don't imagine a warp mutanted primarch but a primarch that has either clearly sided with xenos or has become a xenos plaything. Big E seemed to be forgiving of failure (Angron, Mortarian), being a bit warp touched (Sanguinius, Magnus), or even xenos influenced (Ferrus arms). But never xenos lap dogs.

[@Masamune84]

If I had to take a stab at this, they both fell during the Rangdan Xenocides. If the lore we have on the Rangdan is to believed that these aliens were so dangerous, it could be plausible for the 2 Primarchs fell under their sway for one reason or another

[@gwilym1991]

The mutation/chaos corruption theory fits nicely as Sanguinius says to Horus the reason he's kept his legion's flaw a secret is fear that his legion could be similarly erased, and he seemed genuinely scared of that possibility. Part of me wonders though if the Legion of the Damned is linked to the lost Primarchs.

[@ruthlessasmr6662]

I remember hearing a passage somewhere that says that neither the imperium nor chaos will actually tell you what happened to the primarchs as their fates were worrying enough that neither side would ever speak of them. My personal headcannon is that one likely fell to the Slaugth/Rangdan during the start of the great crusade, somehow tying into the echoing vault. The second potentially may have been something from the "Deep warp" ... Both of those explanations may be reason the emperor and chaos would want their fates suppressed as well as tying into 2 pieces of lore that are also not particularly built up.

[@andrewsuryali8540]

I think rather than go with something bad happened and they had to be expunged, the better story would be for them to be BETTER than all their kin and the Emperor himself. Imagine two Primarchs who were truly idealistic, understood and loved humanity more than their ruthless father and flawed brothers, and dared to imagine a different path. They would then, disgusted by the horrific excesses of the Great Crusade, betray the Emperor not due to chaos influence or trickery but actually to save humanity from what they correctly surmised would have become endless tyranny under their immortal father. Their memories would have been purged not because of their failings but because the Emperor could not afford to admit that a better vision once existed of a humanity more free and dignified, championed by the best of his own sons.

[@jaimeperales7219]

Malcador unlocked the memories of them to Rogal Dorn. I think Valrak did a video on it few years ago. WILD, but honestly love it

[@adams5613]

I liked to think that the forgotten was one that had the moral will to tell the emperor no. To stand against him, not rebellion but rejection. And the purged to be one that, and part of his legion, fell to enslavers. This would be why both were fought against and would account for why they couldn't be spoken about as it would make the emperor not all powerful and would cause doubt on the emperor's plans. This would also allow for the wolves and DA to have fought marines and exterminated a secret. 😁

[@liambewick7523]

My head cannon is that one of the lost Primarchs received a warp based injury that is slowly corrupting him and in order to buy time, the Emperor put him in suspended animation and expunged until he could be healed while the other was driven insane by a warp artefact and also expunged and imprisoned until his sanity could be restored.

[@barryhercules7588]

I liked the idea that their "flaw" was being too good hearted and unwilling to follow through on some of the excesses of the crusade and challenging the Emperors disregard for individual human lives for err the greater good? The greatest threat to the Empire would be its leaders not willing to sacrifice others for its survival, something that could be seen as necessary evil. The idea that the Empire erased its nicest guys to protect the idea they are the good guys is full on grim dark tragedy.

[@T3nch1]

>What could a primarch do that's so bad the Emperor would wipe them from memory? *Sideways glance at Horus Lupercal.* I mean, I can think of something. Xenos integration or defection. If a lost primarch landed on an Ork world, there's at least a 50% chance the child would survive to adulthood and a primarch raised by Orks could easily become a warboss, *and* there's precedent in Orks working with humans and humans adapting to Ork society, see the world of Angelis/Gorkamorka and the Diggas for more on that. But what if a lost primarch ended up in the hands of the Eldar, T'au or other Xenos race that could be potentially friendly to humans? One of the Emperor's sons adapting and adopting xenos culture and lifestyle or genetic mixing with the xenos would be more then enough for the galaxy's worst dad to say that son doesn't exist. Falling to chaos is a warning against turning evil, the Emperor can allow that to be known, but if the primarchs learned they just take their soldiers and leave to join the xenos? Ultrasmurfs would certainly go T'au, White scars are very Orky and Raven Guard would go Aeldari. And then the AdMech would get ideas and go Necron. And the Emperor would allow none of that even a chance to happen.

[@shorney11]

My best two guesses as to what one of them did, raised by Eldar or other Xenos and chose to side with them in a war, Chose to not lead a legion and go his own way.

[@bodiewisehart4703]

I like to agree with the idea that one of the lost Primarchs is still around outside the galaxy. If I recall correctly one of the traitors in the heresy heresy novels mentions that a lost primarch stumbled upon some necron ruins in the past. I think these ruins allowed the primarch to explore past their galaxy (against the emperor's wishes) and therefore was expunged from records. This way I can imagine a return with legion strength ( maybe some lost dark age tech) and making another faction at war with the imperium (since lost primarch and Big E never saw eye to eye).

[@steverobinson1512]

Another great one Rho! I believe that the word ‘tragedy’ does not necessarily mean what most people use the word for. The fall of Horus was a ‘tragedy’ …but anyways, I believe that these two were sacrificed to the Ruinous Powers. I theorize that the Emperor used the warp and maybe …some promises to the Ruinous Powers to help create the Primarchs…and they come to collect.

[@MrJordwalk]

I don't agree. It isn't a coincidence that 9 Primarchs and Legions betrayed the Imperium, as 9 is Tzeentch's number and I say 9 Primarchs instead of 10 because ONLY ONE of Alpharius and Omegon truly betrayed the Emperor IMHO. I also find it more sensible that the Ruinous Powers demanded A STEEP price for the knowledge The Emperor wanted.

[@MrGlobbits]

I'd like to believe it wasn't either chaos corruption or going traitor, as those are just too expected. But something else enitrely, because that's more interesting.

[@mikeprice5755]

In the real world I’m pretty sure that once the black library became more popular the decision to keep 2 legions as blanks just gave authors the opportunity to mess around (by agreement im sure) and drop teases etc. Always leave them wanting more. No way that any explanation will be good for GW & BL as everyone wants something different. In the 40k universe I like the idea of a null / blank pariah primarch although IDK how that could be achieved with their creation being reliant on warp tech / chaos. Also probable that their appearance in any system in real space would just cause billions of heads to implode. Female would be interesting too but unlikely.

[@LuoSon312_G8]

what if one of the lost Primarchs was in fact "The Beast" creating an unintended champion of the Gork and Mork. Whisked away before their "death" only to return after the Heresy, and failing to reunite the Galaxy and the fracturing Imperium.

[@chriscarrillo6649]

I like to think 11 was erased for 4 things. 1he obsessed over wanting a family of his own, sometimes leading him down dark paths in search of it. 2 he wielded a demonic blade from Zeetch. 3 he implanted a possible AI in his flag ship.4 he captured a craft world and was trying to intergrade them..... All of this ending with him creating a half primarch and half eldari being he could call his child. The emperor could not let this be known to the others , also knowing 11 would fight to the death for his child.

[@real-lomas-chenko]

The second son leads my legion 👀👍 And it's interesting how you mention them being other heads of the hydra when I chose the alpharius model to represent him

[@xainkuze2338]

I agree with your theory involving that the primarks were not killed but merely deleted to ensure that chaos or any other group would not know of their names or their assignments. I believe that the two lost primarks are out there dealing with the bulk of the tyranid hive mind fleet. I don't know much about the Lost prime much but there is some lore one on the 11th saying that he was amongst the most innocent of the primarks, not to mention that at the time the 11th Primark was created the anti chaos God Malao was still around and that his number that represented him was 11. And as for the the second Primark, information on him says that he was incredibly cold logical and stern more so than Rogal Dorn ever could be.

[@derpymantis8488]

Maybe the lost primarchs found some old records that belong to one of the many churches that were destroyed in the unification of Terra and delved further into a old belief even sharing their findings with their respective home worlds before getting all information of them is erased or chased out of the galaxy

[@saltedllama2759]

In the Siege of Terra series - easily the best part of the entire HH thus far, and 100% canon - we learn that there were originally 25 test tube babies. Erda, a perpetual and friend to Big E for thousands of years, is who scattered them using tremendous psychic powers (a la the Warp). She went into hiding, but he never pursued or punished her for it. Valdor is a Primarch in all but title, as his stature and abilities are very similar. But because his role was never to participate in the Crusade, and he was around before them, it rules him out as one of the test tube creations. It's possible the Emperor reserved a few as test runs or other projects, or that a few of them simply failed to manifest. The two which were lost and/or forgotten could have been scattered and simply never recovered, or were beyond recognition, repair, or even life, when he did find them.

[@kingbaldwiniv5409]

Don't forget that Fulgrim said the 2nd had no detectable sense of humor (Fulgrim's primarch novel), and that Horus railed against their erasure on the grounds that they were honorable warriors that fought for the Great Crusade and Imperium (short story, The Last Council). This indicates to me that they that they had succumbed to something other and other than strictly chaos. One may have gone entirely crazy, the lost, while the other may have sided with Xenos against humanity, the damned. The Lion fought the Rangda and the Krave, while Sanguinius and Horus fought the Nephilla, each with strange mind control or illusory power. The timetable and location seemed to indicate the lost and damned being dealt with around the Rangdan Xenocide. I find this to be a fairly good hint the hint at what may have befallen them.

[@michaelnims6264]

I think that the forgotten legions were purged from the record due to their gene-seed being so aberrant, and their flaws so severe that they could not be overlooked. This explains why Magnus was so terrified of his legion being erased one day due to the flesh change. When Horus and the traitor primarchs fell to chaos, it reflects on their own failings and personality flaws. If there was a flaw in the gene-seed so severe that two entire legions and their Primarchs had to be destroyed, this reflects poorly on the Emperor himself and on the Astartes project overall. I believe this is why they were erased from the record while the traitor Primarchs were not.

[@overgrowndwarf1628]

Cawl has stated that the gene-seed is stable and free of any mutations.

[@michaelnims6264]

@@overgrowndwarf1628 he did, and he also claimed that the Blood Angels would be free of the Rage, but this was not the case. Cawl is arrogant, and not everything he says is to be believed.