Gulag
07-13-2010, 09:48 AM
what follows are my notes for an Alternate Heresy in the 40k universe. I'm hoping that some comments and feedback might help me refine it down a wee bit more and break the writers' block I've got going on.
WARNING: notes may be rough.
The Heresy TL outline
POD: The Warp alters the character of the Primarchs - Sanguinus is less noble, Konrad Curze is more noble but more insane, the Lion is deeply corrupted, and Horus becomes more stalwart in the face of Chaos etc.
The Lion is unconsciously corrupted by the powers of Chaos, without obvious physical flaw but deep emotional and character flaws that he constantly struggles to keep at bay.
Events continue very similar to canon with minor exceptions like the death of Kor Phaeron and the influence of Chaos on Lorgar and his chastising by the Emperor and Fulgrim never takes up the Laeran blade.
Horus is named the Warmaster as in canon, but here the Lion campaigns covertly to have him step down or be overturned by his brother primarchs in favor of the Lion. This mission fails miserably, alienates the Lion from a few key Primarchs and makes El'Jonson deeply bitter.
Some time before the powers of Chaos seek to convert Horus, Luther and Lord Cypher show that Caliban's taint runs as deep as the Lion's own secret corruption and that to allow Caliban to be destroyed for that taint would be to allow himself to be destroyed as well. For his own selfish reasons, the Lion becomes complicit with the use of the Dark Powers to conceal the taint in his Legion, on his homeworld and himself. This leads to the Lion accepting his dark side and becoming a tool of Chaos while still believing himself to be loyal to the Emperor. Luther and Lord Cypher have no such delusions and plot accordingly with the corruption of the Legion going on over many many years, so that there are few if any Loyalists by the time of the Heresy.
When it comes time to turn Horus to the Ruinous Powers, the Lion is almost fully corrupted except for his own delusion of loyalty and using the darkness for good things. Horus resists turning and borders on death - the Chaos Gods want Horus to turn and become the leader of the potential Traitor Legions, more than they want the Lion to and when they turn to the Lion to try and convince Horus to convert in the spirit vision, the Lion instead out of greed, ambition, selfishness, etc. gives Horus the proverbial push down the stairs that results in the Warmaster's death.
This is the final act that truly damns the Lion, though he continues to deny it. The Powers of the Warp are surprised that the Lion would disobey them, but at the same time revel in his fall and treachery, knowing that he is really the right tool for the job.
After Horus dies, his legion goes into super mourning seclusion and the Great Crusade stalls out - everyone is shocked that a Primarch could be struck down. Big hoopla over it - and through his old connections and track record for victory, the Lion gets his wish and becomes the new Warmaster. Being a vindictive prick, he reorganizes the Legions loyal to him to rewarding positions, with much help and counsel by Luther and Lord Cypher.
Luther and Cypher have been covertly establishing connections with Legions who have already fallen to Chaos or are ripe for it and doing so in the Lion's name.
When the time comes, I believe it will be started by Magnus trying to warn the Emperor like in canon, and the Space Wolves being sent to punish them but things don't go as planned and the SW's take a serious beating from the pre-warned Thousand Sons fleet (courtesy of Luther or Cypher). Magnus and Leman Russ are both assumed dead in the intense fighting that sees heavy losses on both sides before the Thousand Sons withdraw into the Warp.
In the immediate aftermath of the Magnus Incident Konrad Curze confides in Fulgrim about his visions of the future and his myriad prophecies. In the wake of the events on Prospero this news is treated much the same - the Night Lords and Konrad Curze are summoned to stand trial and be judged by the remaining Primarchs.
The Night Lords turn and flee, firing on and destroying the Imperial Fists and Emperor's Children vessels sent to bring them to trial, retreating to Nostramo.
Learning the lesson of sending a single legion to bring another legion to trial, the Lion sends the massed strength of the Iron Hands, White Scars, Raven Guard, and Emperor's Children to bring the Night Lords to justice.
The first overt act of the Heresy would be several simultaneous attacks on multiple targets across the galaxy:
Ambush of the Loyalists over Nostramo by the Tzeentch-sworn members of the Emperor's Children in concert with a maddened assault by the Night Lords. The ambush does not go as well as hoped, and in retreat the EC unleash a psychic plague on the Loyalitst astropaths and navigators, killing or incapacitating all of them and temporarily stranding the White Scars, Raven Guard, and Iron Hands far from Terra. To further damage the stranded loyalists, the retreating Night Lords fire on the weak point in Nostramo's crust and cause it to explode, taking with it a number of Loyalist Marines who had occupied the world in the false belief that the Night Haunter was holed up there.
Brutal and ruthless surprise attacks on the Ultramarines by the World Eaters which keeps them from moving to relieve Terra. The Alpha Legion is busy helping the Ultramarines and cannot send serious support to Terra.
Sons of Horus leave their isolation of mourning and grief, emerging changed and blighted but at the same time strengthened, attacking the Salamanders and Nocturne, drawing them away from Earth into a long bloody stalemate.
Dark Angels arrive over Fenris, to the Lion's surprise as he has been temporarily confused/whatever by sorcery and when he returns to his senses, he is bombarded by reports of the widespread attacks and treason in his name. Furious at Luther, Cypher and the Dark Gods, he has no choice but to proceed. To signal his cooperation, he orders the Exterminatus of Fenris. He is joined by the forces of the Blood Angels, Iron Warriors, and Death Guard in his advance on Terra.
The Word Bearers, hearing of the betrayals by the forces sworn to the Lion, rush to Terra and join the Imperial Fists in preparing the defenses in the Sol System against the approaching forces of the Second Warmaster. There are clashes between the leadership styles of Rogal Dorn and Lorgar about how to defend the Sol System, but in the end, Lorgar accedes to the Emperor's Praetorian's defense plans.
When the Traitor Legions arrived in the Sol System, they were met by Loyalist space forces who attacked them as soon as they arrived, and but were forced to recreat as the superior weight of the Traitor Legions and the Lion's brilliant strategic skill made the battle bloody and one-sided. This came at the same time as the Fall of Mars to the Dark Mechanicum who declared their support for El'Jonson.
In this dark hour, the battle-scarred elements of the White Scars stranded at Nostramo arrived, having sacrificed their Librarians to guide their vessels through the Warp, at the cost of the sanity and lives of their Stormseers.
Loyalists fall back to Terra, and the defenses of Luna are smashed, along with the Loyalist fleet.
Traitors bombard and then land on Terra. Fighting ensues with the battle stalling out to a siege of the Imperial Palace, with the Fists and Word Bearers holding the walls while the White Scars to hit-and-fade missions to stall out any advances.
Iron Warriors & Blood Angels attack and attempt to breach the Eternity Gate but are held by Lorgar who stands alone against the assault, until while locked in combat w/ Sanguinius, he is stabbed in the back by Perturabo.
However, this victory is overshadowed by word that the Alpha Legion and Ultramarines have broken through and scattered the World Eaters and are driving on Terra. Even the battle-scarred and decimated Space Wolves have reached the stranded Iron Hands and Raven Guard and will see them arrive shortly after the AL & Smurfs.
Being less of a gambler than Horus, the Lion uses Sorcery/Warp mumbo-jumbo to lure the Emperor, Rogal Dorn to his Flagship only to find the Lion isn't present and its a trap - the warp drives are tainted and explode in waves of dark energy that kills or corrupts more than half of the forces on board. Dorn is spared, but the Emperor is horribly maimed. Dorn grabs the comatose Deity-Sovereign and bugs out while the ship comes apart.
El'Jonson knows his trick failed to kill the Emperor and orders his Dark Angels to disengage over the objections of Luther. His forces initiate a surprise fighting retreat, keeping the overwhelming majority of his forces intact. The Blood Angels and Iron Warriors on the other hand, take heavy casualties during the surprise retreat. This ensures that though the Lion lives, none of the other traitor legions will ever trust him again.
The Emperor & Dorn land on Terra and the crippled Emperor tells Dorn that he is physically crippled and how to make the Golden Throne a life-support system to keep him alive and tie his mind into the Astronomicon. Though he lives, the Emperor can no longer lead the Imperium or even communicate with his Sons. He is forced to spend the majority of his focus, power, and effort to keep himself alive and his warp-tainted injuries from killing him. The Emperor has the theoretical ability to communicate and interact, but between the Chaos attack, the failure of his primarchs, and the degeneration of the Imperium into everything he was fighting against he doesn't except in very extreme situations. Instead of just the Astronomicon needing regular infusions of pyskers to work, the Imperium instead sacrifices a horrifying number of psykers to boost the Emperor's strength long enough for him to tell them how to handle a particularly horrifying event - like the Tyranids or such. Any interaction with the Emperor is very brief, cryptic, and confusing - not to mention dangerous to the Emperor who must take a fraction of his attention from his injuries, and to whoever by necessity must be present in the Throne Room when such absolutely titanic psychic energies are unleashed.
LOYALISTS
The Penitent Sons (a major pain to write this up in a clear manner)
When the majority of his legion turned Traitor, Fulgrim was left stranded with a small core contingent of Loyalists as the Traitors led by Fabius Bile looted the Legion armories and seized or destroyed all of the Legion's accompanying ships. After the Heresy, Fulgrim and his loyalists were recovered from their brief exile and placed on trial by the surviving Primarchs. Only Ferrus Manus' intercession prevents the complete disbandment of the Legion but they punishment they receive instead is far harsher - the Loyalists are stripped of the right to wear the aquila or indeed any insignia and are forced to perform exterminatus on Chemos and undertake a crusade for penance. While on this crusade, the Emperor's Children would be banned from taking new recruits for 100 years. After leaving the ashes of Chemos behind them in a few salvaged ships, the loyal Emperor's Children changed their name to the Penitent Sons as a sign of their great guilt.
To prove their devotion to the Imperium and atone for their past failures, the Penitent Sons perform regular ritual scarification of their faces while having their oaths of service tattooed into the flesh of their chests. As the tattoos and scars fade, they are re-applied so that the symbols of their dedication never wane.
Doctrinally, the Sons have abandoned their past quest for perfection and become ultra-specialized, and in their quest for redemption of their predecessors' sins the sons of Fulgrim seek release in close combat bringing death to the enemies of the Emperor with bolt pistol and chainsword. Many, if not most, battle brothers have a death wish of various strength and eagerly seek out battle without fear or hesitation.
The loyal survivors of the Third Legion embraced the Codex Astartes proposed by Roboute Guilliman with a fanaticism that is unmatched. The only deviation initially allowed by Fulgrim and his fellows is a total ban on psykers within the legion as warpcraft had brought about their downfall once before. Over time, necessity has forced them to modify their adherence to the Codex as the Penitent Sons suffered combat losses they were unable to replace. At the end of their 100 year ban on recruiting, the Sons were forced to accept both Inquisitorial and Nightwatch approval for any new recruits. This laborious process ensured that the Penitent Sons could not replace their numbers as fast as they lost them.
The attrition of the constant campaign and self-castigation would have meant the end of the sons of Fulgrim if not for their actions in M36 that brought a swift and sudden end to the Age of Apostasy. The forces of the Renegade Bishop Bucharis had been driven back to their capital on the planet Gathalamor but the end would not come quickly as the renegade naval vessels loyal to the Cardinal formed a defensive cordon around the world and repelled repeated attempts to force a breach and land troops. The stalemate remained in place until the sudden arrival of the Penitent Sons who had been reduced to only 400 astartes and a single battle barge the Lash of Punishment.
Without warning or indecision the Lash dove through the renegade naval vesses, ignoring the weight of their fire to emerge over the Cardinal Palace and unleash the entire complement of the Penitent Sons in drop pods regardless of the consequences, even as their void shields fell and the mighty battle barge exploded.
The ensuing battle to take the Palace would be one of the most costly and important for the Penitent Sons since their betrayal during the Heresy with barely half of Astartes living to see the fall of the Palace and the end of Bucharis' rule. The sacrifice of the Sons was noticed by the powers of the Imperium, and for their actions the sons of Fulgrim were granted permission to recruit initiates for rebuilding and to eventually establish successor chapters.
Even after centuries and even millenia of crusading their loyalties remain suspect by the Imperium at large which has seriously affected their equipment - their Terminator armor, confiscated during their trial after the Heresy, has never been returned. The Penitent Sons have remained the least likely Chapter to receive new or repaired equipment and vehicles. With few vehicles left those that they have remaining are only sent into battle in dire need. The Sons have at best three Land Raiders left for all their forces and Rhinos are almost as rare with no new vehicles, such as Razorbacks, to replace them.
With the severity of his punishment and the magnitude of his failure, Fulgrim sought to emulate the demeanor of his closest brother's Iron Hands Legion. This has led to the Penitent Sons exhibiting a demeanor of curious mixture of conservatism, fatalism, and brutality that became the foundation of their reputation among Imperial units as the most brutal Astartes Chapter.
Though Fulgrim physically survived the Heresy, it could be argued that his spirit did not - in the years and centuries to follow he lapsed into an ever deeper spiral of depression, self-loathing, and self-pity whereupon he would spend hours and eventually days punishing himself in the embrace of a pain glove. The end would finally come for the broken Primarch during the Great Scouring in a battle to take a damaged Strike Cruiser belonging to the Blood Angels attempting to reach sanctuary in the Eye of Terror. During the course of the battle, one of the Traitor Astartes struck down the Primarch with a daemonic blade from behind. Even with the death of their Primarch, the Penitent Sons pushed forward and eventually purged the vessel of all foes before destroying the ship with demolition charges.
Primarch - Fulgrim - dead shortly after the Heresy.
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Space Wolves
The Sons of Russ only barely resemble any adherence to the Codex after the disappearance of Leman Russ on Prospero while locked in mortal combat with the Traitor Primarch Magnus the Red. The loss of Russ would only be surpassed by the destruction of Fenris by the traitors of the Dark Angels.
After the Heresy, the Space Wolves have become a scattered Legion divided further into successor Chapters with many Great Companies operating completely independently of their chapter hierarchy.
Even without Fenris, the Space Wolves still want to keep inducting blooded killers into their ranks so they start going for the most concentrated collection of killers possible - the Imperial Prisons. With great intent the Astartes begin beating their Fenrisian culture and heritage into the heavily tattooed prison scum that make up their recruits. Their new recruits have lead the Wolves to become even more savage and barbaric in battle than before, approaching the infamous brutality of the Pre-Heresy World Eaters.
Primarch - Leman Russ - Believed alive but lost in the Warp, possibly locked in eternal battle with Magnus the Red.
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The Faithful
Following Lorgar's death in the defense of Terra the surviving Word Bearers become similar to a cross between the Doom Eagles, Black Templar, and Mortifactors. The death of their Primarch and the crippling of the Emperor will make them go crazy and they're going to go on constant attacks on the retreating traitors regardless of the losses. They draw out the more fanatical and religious elements of the other Loyalist Legions like the predecessors to the Doom Eagles, Black Templar, and Mortifactors to join them and the combined force takes up the name the Faithful.
This lets the surviving legions purify themselves of superstition and let the fanatics reduce their own numbers while hurting the enemy. This works by the end with the Faithful being much reduced in number but has the unwanted side effect of making Emperor Worship universally widespread and the official and enforced State Religion of the Imperium.
Dorn and Guilliman had no problem offloading their problems to die honorably while removing a potentially serious threat to the stability of the Imperium. They don't see the inevitable gene-seed degeneration in the Word Bearers as such because they instead see it as injecting some higher quality elements to Lorgar's ignorant genetic soup. The end result is a nice twist on the usual Black Rage - like Dorn's successors, their sus-an membrane doesn't work, so they can't go into suspended animation and a mutation in the Preomnor implant alters the neuro chemical balance of the brain over time that results in a steadily increasing focus and perception of time and space which causes their reflexes to become steadily faster until they give the impression of mild precognition. This comes at the progressive loss of self as a marine becomes nothing more than a living combat weapon who eventually will not care for themselves at all - they won't eat, drink, treat their own wounds, sleep, talk and at the deepest levels they will completely stop breathing and simply die. The only way to keep them functional in the latter stages is their intense hypno-doctrination and ingrained combat training and muscle-memory. The Astartes of the Faithful call it "the Sorrow".
The large numbers of Marines succumbing to the Sorrow has lead the Faithful to field large numbers of Dreadnoughts in lieu of vehicular support, but these dreadnoughts differ from their kin in that that they need the guidance of a chaplain to remain in control and be directed on the battlefield - without that constant guidance they will set out on their own to attack the nearest enemy on the battlefield with no organization or control.
Primarch - Lorgar - killed by Perturabo on Terra
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Raven Guard
In this alternate heresy the Raven Guard were not decimated at Istvaan-equivalent, which means that they were fully engaged in the post-Heresy pacification of the Imperium. This means that while some of their stealthy/guerilla doctrines are still around, they might have had to resort to more straightforward tactics. Their covert warfare experience made them more adept at infiltrating fortifications and taking them, giving them much different skill set in the long run. Additionally, it gives them much more merciless attitude, which eventually leads Corax to leaving for the Eye of Terror, ostensibly on a mission of revenge, but really because he saw he was becoming just like the people of Lycaeus/Kiavahr before he showed up (which means he will be missing, presumed dead).
As a result, the Raven Guard are much closer to the canon Imperial Fists or Dark Angels, and while some minor mutations exist in their gene-stock, they are considered to have one of the better, more dependable lines of gene-seed. They are also the Chapter/Legion of choice to call upon when fighting insurrection, and, while relatively humanitarian outside of war, they can be utterly relentless and brutal in war, to where anything goes for accomplishing victory. This would lead some Imperial Army regiments to refuse to fight alongside the Raven Guard, who wouldn't think twice about sacrificing their erstwhile allies if the need calls for it.
The needs of suppressing the post-Heresy rebellions causes them to adopt more Terminator squads, and take a somewhat non-Codex organization, in that they will be less specialized as a Chapter, but more specialized on Company level. They would have dedicated "guerrilla war" companies, dedicated "heavy assault" - read Terminator - companies, dedicated "fast attack" companies - completely composed of Assault Marines and bikes, etc. The idea is that a Raven Guard force has many different Troops choices and army configurations available to them, but the actual army structure is heavily dependent upon which doctrine they choose at the onset of battle, perhaps through the HQ character they deploy.
This way, a Raven Guard army could play similar to Dark Angels Deathwing, they could play somewhat similar to canon Blood Angels (with Assault Marines taken as Troops, and supported by bikes, which is a Raven Guard difference from Blood Angels), or they could take an all-scout force (unique to Raven Guard). The drawback is that this doctrine is VERY specialized, and generally has severe limitations; while they can put together a basic, all-around force, they will do so at the cost of being unable to include special HQ characters, having to make do with a very generic Captain or some such.
Primarch - Corax - missing, presumed dead
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White Scars
The White Scars are a lot like the canon Space Wolves, albeit with a few successors (due to reasonably decent gene-seed), and perhaps little more pliable to the Codex than the Wolves. Still bike-mounted, with perhaps Ravenwing-like formation (which can be accomplished with canon White Scars as well), but also focus on Land Speeders and the like, with a unique unit that is basically a jump-pack Devastator squad (i.e. heavy firepower and mobility, disdain for close combat).
Primarch - Jaghatai Khan - Unknown location
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The Salamanders
The Nurgle-infested Sons of Horus are sent to attack Nocturne while the Salamanders are away in the first hours of the Heresy. This would basically exterminate most of Nocturne's population, and force the Salamanders to kill the rest of their people when they return to expel the SoH.
Killing plague zombies that were your charges until now has resulted in a very, very grim Chapter.
The Salamanders have a massive guilt complex, and would take their humanitarian streak to even higher extremes. While they would attempt to repupolate Nocturne, they would turn it into a "refuge planet", which, in turn, would mean they will accept people not wanted anywhere else in the Imperium - psykers, some types of mutants, refugees from many of the Imperium's wars...
The Salamanders would end up running a small empire centered on rebuilt Nocturne (and having anywhere from 5 to 10 systems), which will be arguably a nicer place than most of the Imperium, but not without its price. The lack of genetic conformity in their recruiting population, high levels of radiation on Nocturne, and the need to rebuild after the Heresy might have resulted in some degradation of their gene-seed that has seen some increased functionality in certain implants and mildly decreased functionality in others.
Because of their degrading gene-seed and accidental empire-building, the Salamanders are somewhat distrusted, and there are very few Chapters made with Vulkan's gene-seed. The general Imperial consensus is that the Salamanders serve a useful purpose with the Realm Of Fire (i.e. TTL's Ultramar) and have proven loyal, but are very close to the line of what is acceptable (in how they actually dare to treat their subjects WELL), and therefore should not be made any more powerful.
Primarch - Vulkan - disappeared with his First Company Veterans into the Eye of Terror pursuing the Sons of Horus during the Scouring.
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The Imperial Fists
After the Heresy, the Imperial Fists became divided between three conflicting visions - that of the Faithful who attracted the more religious members of Dorn's Legion such as Sigismund the Emperor's Champion, that of Guilliman and his Codex Astartes, and that of Dorn. Most of the legion stayed loyal to Dorn's vision and followed him on a mission to drive the Iron Warriors from their fortress on Sebastus IV in the Iron Cage incident where Dorn's arch nemesis Perturabo outsmarted the architect of the Imperial Palace. In the bloody ambush on the planet's surface the Fists held out for days cut off from supplies or support, even after the death of Rogal Dorn in a failed counterattack. It appeared that Dorn and his most loyal Astartes were to die there until the arrival of the members of the Imperial Fists who had split away from the Legion to follow Guilliman's Codex.
With their primarch dead and their numbers dangerously low, the Imperial Fists were desperate to regain their lost honor and return to the service of the Emperor. In their haste the Fists used dangerous and careless methods to produce gene-seed faster and mature recruits with record speed - in the end the shortcuts rendered as many as five different implants non-functional with other organs threatened with failure. Faced with the threat of total collapse, the Fists appealed to their brothers in the Guilliman-inspired successor chapters for donations of their gene-seed to prevent further degradation and mutation. This arrangement has left the Imperial Fists constantly under strength and resentful of the Codex Successor who in turn resent the Fists for their failure in the Iron Cage Incident and for the steady loss of Gene Seed. It is something of an open secret that the Inquisition only tolerates the Fists degradation because of their status as a Found Legion.
With their weakened condition, Imperial Fists doctrine has placed ever greater emphasis on ranged firepower and the avoidance of close combat wherever possible.
Primarch - Rogal Dorn - killed in the Iron Cage incident
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Ultramarines
The only change is less insistence on the Codex organization, making the Codex a suggestion rather than an order for the most part. Certain things would still be enforced (i.e. keeping the Chapters at roughly 1,000 men, although there will be several exceptions, such as the Faithful - initially at least, until constant attrition depletes Lorgar's lot to more manageable levels), but some other things, such as tactical doctrines, might be a bit more flexible.
I would see the Ultramarines as being fairly similar to canon, although they would have had LESS influence on the Imperium at large due to stronger, more organized opposition to Guilliman.
Though Alpharius would be the first High Lord of Terra, Guilliman would serve as the Lord Commander of the Imperium's Armed Force. Guilliman's proposed Codex Astartes would find limited acceptance by his fellow primarchs whose organized resistance to the Codex's strict principles forced a compromise whereupon the Codex has become a guideline to follow and not a binding ironclad document. As such there are few strictly codex chapters, the most notable being the Ultramarines themselves, and the successor chapters of the Imperial Fists being the other most notables.
After the end of Alpharius' term as High Lord of Terra and subsequent disappearance Guilliman became the new High Lord of Terra. The Primarch of the Thirteenth Legion would have a very short reign as High Lord before being assassinated by a Chaos-tainted Callidus Assassin, and his dying body enthroned in a stasis field on Terra.
After the death of Guilliman, the position and authority of the High Lord of Terra was dispersed among several positions so as to prevent a single individual having absolute power over all organs of the Imperial government - though the High Lords are forced to meet in the presence of the enthroned Primarch, who is said to see all and hear all said by the High Lords. Just prior to the Age of Apostasy, a High Lord known for his greed and corruption mocked the fallen Master of Macragge, calling him the "Emperor's representative". That night, the High Lord was found in his chambers murdered in a most horrible fashion, and his many material possessions destroyed. At the next meeting of the High Lords, the disrespectful Lord's tongue was delivered by an ancient servitor, skewered on a gold spike in the shape of an Omega. After this event, the High Lords of Terra assiduously avoid any implication of corruption or disrespect.
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Iron Hands & the Adeptus Mechanicus
The Fall of Mars to the Traitors during the Heresy was a great loss to the Loyalists in the build up to the Siege of Terra. After the retreat of the Traitor Legions, it fell to the Iron Hands to "liberate" Mars from the Chaos-tainted Dark Mechanicus.
The swift fall of Mars and the generally good state of its infrastructure found during its recovery lead to a considerably amount of resentment, suspicion and outright anger by the Loyalists in regards to the Adeptus Mechanicus as a whole.
To repair the damage done to the Red Planet during its occupation and to "restore everything to its proper place" High Lord of Terra Alpharius and Lord Commander Guilliman agreed to name Ferrus Manus as the Regent and Interim Administrator of Mars. The move was exactly as it appeared to be - a symbol that the Primarchs believed they could not trust the Adeptus Mechanicus.
This act almost brought about another crisis as the Forge Worlds and domains of the Mechanicus across the Galaxy that had remained loyal during the Heresy threatened to secede with such a clear breach of trust and a violation of the Treaty of Mars. To prevent an outbreak of civil war so soon after the events of the Heresy, Alpharius brokered a deal - the Mechanicum on Mars would remain under the authority of Terra and its appointed Regent for 100 years before returning to its own administration. As a result the Mechanicus would gain more independence, a greater role in the Imperial military affairs, and two representatives among the High Lords instead of one - one from Mars, and one from the other conglomerates of worlds that are NOT directly controlled by Mars.
This agreement placated the non-Martian Mechanicus and over time has lead to a de facto division within the Adeptus that has carried on even after the departure of Ferrus Manus from his role as Regent - the Martian Mechanicus, which remains closely tied to Terra, and and the non-Martian Mechanicus, which pays lip service to Mars, but, due to the above agreement, acts with far more independence. In fact, there are entire sectors of the galaxy that are given to this Mechanicus to govern, which makes them more or less a no-go territory for the uninvited (i.e. other Imperial organizations, with very few exceptions).
This division has lead to a mild schism within the production qualities of the two factions - the Martian splinter remains very traditional but supremely efficient, producing everything from bayonets to bolters for the Imperial Army and the Astartes with no deviation from established patterns. The independent Mechanicus-realms on the other hand are known to produce small quantities of unique or improved equipment in exchange for a variety of services or needs on the behalf of friendly Imperial Army regiments and Astartes Chapters. This friendliness comes at the price of cooperation with the Martian Adepts, who are well known to punish those friendly units with very slow equipment deliveries and "accidental" logistical errors.
The Adeptus Mechanicus were not the only organization to emerge changed from Ferrus Manus' tenure as the Regent of Mars. During his time as the Interim Administrator he freely "borrowed" designs and equipment from the Mechanicus stores and knowledge to enrich his own Legion. His Astartes became equipped with the newest patterns of armor, bolters and vehicles while their doctrines shifted to include massed formations of armor supported by copied designs from the Legio Cybernetica. These copies of the Martian combat robots march to war side by side with the ranks of tanks, dreadnoughts, and artillery now favored by the 10th Legion during battle.
Their good fortune with their re-equipping and re-training after their time on Mars has seen the diminishing of their more ruthless and unforgiving aspects and the rise of a somewhat noble character, though the Iron Hands remain above all else, Astartes.
Some time after leaving Mars, Ferrus Manus disappeared from the known galaxy. Many rumors insist that the Primarch has returned once more to Mars where he resides in secret, but the Martian branch of the Mechanicus and the Iron Hands both deny these rumors.
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Alpha Legion, The Holy Inquisition, and Nightwatch
After the events of the Heresy, and the crippling of the Emperor, Alpharius, Primarch of the Alpha Legion became the temporary High Lord of Terra and political leader of the Imperium by the agreement of the surviving loyal Primarchs and the mortal leadership of the various branches of the Imperium. Alpharius was selected as a compromise candidate with no strong connections among the Primarchs save for the deceased Horus. Alpharius was also the candidate favored by the Primarchs opposed to Guilliman's proposed reorganization of the Legions into regimented Codex Chapters - Guilliman himself did not oppose the move, as the two former rivals had largely closed the rift between them during the events of the Heresy. As High Lord Alpharius opposed the stricter elements of the Codex Astartes but supported the separation of the Legions into thousand strong Chapters. The large numbers of the Alpha Legion and Ultramarines has lead to each accounting for a third of all successor chapters with the other loyalist legions making up the remaining third.
During his temporary appointment as the High Lord, Alpharius was instrumental in the establishment of the shadowy secular organization known as Nightwatch, which concerned itself many covert operations across the Imperium, mostly focusing on Xenos, and the Traitor Legions while only barely dealing with the issues of mutation, small-scale treason, or religious heresy.
The Nightwatch's lack of outright piety and support in suppressing religious dissent eventually leads the Ecclesiarchy to establish the Holy Inquisition with the support of enemies of Nightwatch who resent its power in the Imperium's armed forces. The Inquisition is a ruthless, brutal and religiously organ but has sole focus on mutants, heretics, small-scale treason, and fighting daemons with the Nightwatch energetically maintaining its own jurisdiction which the Inquisition reciprocates. Something of a shadow war constantly takes place between the two organizations as they vie for power in the Imperium and seek to undermine the other while carrying out their mandated missions to protect the Imperium at the same time.
Despite claims to the contrary, the Holy Inquisition doesn't have the supreme authority of life and death over all of Humanity, they wield a great deal of power (which is matched by that of Nightwatch). With a long history of non-cooperation from outsiders, the Inquisition has their own armed forces made of up of Frateris Militias, Frateris and Sororitas Templar, Death Cult Assassins, Eversor assassins, and the very secret Grey Knights Astartes Chapter. The Inquisition is NOT subtle or forgiving, is very dogmatic and doesn't allow for much free thought.
Nightwatch on the other hand has fewer dedicated troops, instead recruiting volunteers from Imperial Guard and Astartes. The organization does maintain full-time agents, Callidus assassins, Vindicare assassins, and the specialized anti-psyker Pariah Marines. Compared to the Inquisition, Nightwatch and its members are subtle, manipulative, and shadowy, but allowed a surprising amount of room for free thinking and innovation - rumors among the Inquisition maintain that Nightwatch is the main organ for advancing Imperial technology by stealing and dissecting heretical Xenos tech.
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Imperial Army
Following the events of the Heresy changes were made to the structure of the Imperial armed forces. Many of these changes were made to ensure that no single individual would be powerful enough to ever again to attempt to overthrow the ruling body of Imperium if he turned traitor. To this end the existing Imperial Army was divided between the Imperial Army which is responsible for the Imperium's ground forces and the Imperial Navy which is responsible for the fleets of warships that travel between the worlds of the Imperium.
TRAITORS
Mechanicus influenced Iron Warriors FTW. Cold, emotionless, calculating but still Chaos. Go into combat with combat servitors, arco-flagellants, eversor cyborgs, and even a few Penitent Engines leading the way to soak up fire and casualties or to man the siege works and fortress walls.
Primarch - Perturabo - Injured on Terra, he has since become infused with the Obliterator virus and become a massively powerful fusion of man, machine and daemon. Some sects of the Adeptus Mechanicus secretly worship him as an avatar of the Omnissiah.
Leadership – Perturabo retains leadership of the Iron Warriors overall but very rarely takes to the field of battle, instead leaving his Warsmiths largely independent and in charge of their own Grand Companies.
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The Black Legion of Psykers for Thousand Sons is a good description – in the aftermath of the destruction of Prospero the Thousand Sons have emerged across the galaxy to rescue oppressed psykers from Imperial oppression, even going so far as to organize raids on Inquisitorial Black Ships. Secretly the Thousand Sons are consuming the psychic powers and potential of their freed Psyker recruits to keep themselves stable and generally mutation free. This psychic vampirism would come with the added bonus of getting a brief boost to their powers. I could see them keeping psyker-slaves nearby in battle for a quick pick-me-up and even turning on the weaker members of their warband in very desperate times. They'd be mildly associated with the Dark Powers, but leery of their influence.
Primarch - Magnus died on Prospero, possibly at the hands of Leman Russ who may have died in the ensuing pandemonium.
Leadership – the Thousand Sons were swept into the Warp by the forces unleashed during Magnus’ suspected death and largely scattered. The largest and most cohesive survivors of the Thousand Sons are lead by Ahzek Ahriman and a handful of surviving fellow captains.
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Mortarion decides that the only reason he failed on the mountain top and the Emperor succeeded is that the Emperor had superior technology and used it to its full advantage – so Mortarion instills this idea into his Death Guard that his foot slogging infantry should be armed and armored with the very best equipment available.
For the Tech obsessed Death Guard, I'm thinking lots of Combi-Weapons, customized power armor, plasma pistols and power swords preferred over bolt pistols and chainswords and heavily armed Terminators everywhere for support (IIRC the DG had the most Terminators of any legion) backing up the very versatile DG squads which would including a heavy weapon. For added protection, there would probably be lots of Chaos Warding on their armor and daemonic infusion into everything they have.
Primarch – Alive and active. After the withdrawal from Terra, Mortarion has left his legion on his own quest at the behest of the Dark Powers. His quest has him return at seemingly random intervals to lead his legion in attacks on seemingly worthless or random dead worlds across the Galaxy. Mortarion has also been seen to lead his legion into temporary alliances of convenience with the Dark Eldar to create and stockpile special weapons of a psychic nature for use against mutual foes of the “most ancient and dangerous kind”. Such alliances always end with mutual betrayals and bloodshed at the end of which Mortarion and his Deathshroud bodyguards disappear with whatever new weapons they manufactured with the Dark Eldar.
Leadership: During his long periods of absence, Mortarion has named First Captain Calas Typhon to serve as the leader of the Death Guard until his return.
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The Blood Angels path to corruption and worship of Slaanesh began with Sanguinus rescue and early years on Baal Secundus battling horribly disfigured mutants. This period of time instilled in Sanguinus a loathing of the disfigured mutants and their corruption of the beauty and perfection of the human form. Once elevated to command of the Ninth Legion, Sanguinus passes on this loathing of mutation and human imperfection to his Astartes.
Over time, Sanguinius and his Astartes start to feel unappreciated for all their hard work killing ugliness and imperfection in the galaxy, and the whispers of the Lord of Dark Delights took root, offering great rewards for their dedication.
Once dedicated to the Prince of Pleasure, the favored of the Legion have wings like Sanguinus, though theirs are gifts from Slaanesh. The Blood Angels still strongly favor assault tactics at close range, and to further gift his chosen warriors, Slaanesh has gifted them with a powerful glamor the confuses their foes, and slows their reactions.
Primarch - Sanguinus is alive and active.
Leadership - despite Sanguinius' survival, the Blood Angels are divided into warbands roughly along the lines of Great Companies that rarely cooperate without the direct order of the Blood Angel.
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The Sons of Horus who worship Nurgle after the death of Horus in a long dark despairing depression. Hate and resent everyone else for not protecting or appreciating the fallen Warmaster. The SoH vehicles have all become possessed by daemons, freeing even more Astartes for the battlefield. Like their vehicles, a lot of the SoH are possessed by Plaguebearers, getting a long scythe-like mutant limb for close combat and spreading disease while also producing clouds of flies and bits of foul nastiness that conceal their brethren as they advance across the battlefield.
Primarch - Horus is dead, struck down by the powers of Chaos when he would not convert.
Leadership - after the death of Horus, Maloghurst the Twisted has assumed control of the Legion with the aid of Erebus, the Legion's great religious adviser who guided them after Horus died into the worship of Nurgle. Individual Grand Companies/Warbands swear fealty to Maloghurst.
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The Emperor's Children breakaways lead by Fabius Bile would account for a rather large number of the Legion and would dedicate themselves to Tzeentch on the quest of seeking perfection through mutation, gene-engineering, tissue grafts, and combat drugs. Each member of the EC would gain a powerful Wild Talent that is powerful but hard to control, with failure resulting in severe mutation, madness, or devolving into Chaos Spawn.
Primarch - Fulgrim remained loyal to the Emperor
Leadership - Though Bile is officially in charge of the Legion, he rarely concerns himself regular operations, instead preferring to remain his laboratories and conduct his vile experiments. Warbands are commanded by champions of Tzeentch, drawn from the ranks of fallen Lord Commanders.
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The Night Lords would be torn apart in Civil War when a renegade Night Haunter is driven mad by conflicting visions of the future. Each company and warband of the NL would seek to prevent or ensure the fulfillment of a different prophecy inked by the Haunter before his death. Due to a mildly more noble streak in his character, the Haunter is not a Fear-mongering Terror Junkie but instead a draconian tyrant obsessed with his visions of the future. His Legion has a serious Cassandra Complex and blurs the lines of insanity with random attacks on sometimes totally worthless targets. At the scene of every attack they leave fragments of the Haunter Prophecy their warband/company is working on.
In addition to a toned down skull-and-bat motif of canon, each member of a warband covers his armor in complex Nostroman glyphs telling parts of the Prophecy their warband is dedicated to.
Primarch - Konrad Curze is dead, killed by own Legion.
Leadership - fragmented into warbands of varying sizes.
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The World Eaters instead of going all skulls-and-blood berzerker crazy have a calm, controlled, collected and calculating leadership. Perhaps some of the captains thought Angron was a little too nuts and allowed their lower-level marines to get skull implants while avoiding them personally. During and after the Heresy they herd Angron and his berzerkers into combat while executing their own attacks with the mindless berzerkers soaking up the fire and taking the losses. Over time, the losses in lower level marines and their very short battlefield life expectancies has lead to the leadership cutting corners in recruiting - they use recruits other legions wouldn't use for target practice implanted with badly degraded gene seed and failing clone organs that will fail within a few short years (a result of accelerated gene-seed growth processes and gene seed alterations) but grant the recruits unnatural strength and resistance to harm. The deficiencies in recruits and gene-seed is further offset with the fitting of new-model cranial implants that are inactive until battle is imminent to keep the berzerker-fodder docile while driving the warriors into ever greater rages. Whenever possible, the disposable berzerkers are equipped with the recovered arms and armor of their fallen predecessors and dead foes that has been hastily repaired. Eventually Angron proves to be too great a danger for his clear-thinking captains who can't risk losing him on the battlefield so the Primarch is subdued and lobotomized, trapped as an insensate vegetable for eternity and constantly harvested for genetic material to replace worn-out Gene Seed.
Primarch - Angron is a vegetable constantly harvested for Gene Seed.
Leadership - the Legion is now in the hands of the Captains present after the Primarch's recovery, but as a first among equals, Kharn the Betrayer speaks with the most authority. Kharn earned that moniker as the mastermind behind Angrons brain-panning, which he undertook without the agreement of his fellow captains. He is feared, loathed, respected, and admired in equal measure.
WARNING: notes may be rough.
The Heresy TL outline
POD: The Warp alters the character of the Primarchs - Sanguinus is less noble, Konrad Curze is more noble but more insane, the Lion is deeply corrupted, and Horus becomes more stalwart in the face of Chaos etc.
The Lion is unconsciously corrupted by the powers of Chaos, without obvious physical flaw but deep emotional and character flaws that he constantly struggles to keep at bay.
Events continue very similar to canon with minor exceptions like the death of Kor Phaeron and the influence of Chaos on Lorgar and his chastising by the Emperor and Fulgrim never takes up the Laeran blade.
Horus is named the Warmaster as in canon, but here the Lion campaigns covertly to have him step down or be overturned by his brother primarchs in favor of the Lion. This mission fails miserably, alienates the Lion from a few key Primarchs and makes El'Jonson deeply bitter.
Some time before the powers of Chaos seek to convert Horus, Luther and Lord Cypher show that Caliban's taint runs as deep as the Lion's own secret corruption and that to allow Caliban to be destroyed for that taint would be to allow himself to be destroyed as well. For his own selfish reasons, the Lion becomes complicit with the use of the Dark Powers to conceal the taint in his Legion, on his homeworld and himself. This leads to the Lion accepting his dark side and becoming a tool of Chaos while still believing himself to be loyal to the Emperor. Luther and Lord Cypher have no such delusions and plot accordingly with the corruption of the Legion going on over many many years, so that there are few if any Loyalists by the time of the Heresy.
When it comes time to turn Horus to the Ruinous Powers, the Lion is almost fully corrupted except for his own delusion of loyalty and using the darkness for good things. Horus resists turning and borders on death - the Chaos Gods want Horus to turn and become the leader of the potential Traitor Legions, more than they want the Lion to and when they turn to the Lion to try and convince Horus to convert in the spirit vision, the Lion instead out of greed, ambition, selfishness, etc. gives Horus the proverbial push down the stairs that results in the Warmaster's death.
This is the final act that truly damns the Lion, though he continues to deny it. The Powers of the Warp are surprised that the Lion would disobey them, but at the same time revel in his fall and treachery, knowing that he is really the right tool for the job.
After Horus dies, his legion goes into super mourning seclusion and the Great Crusade stalls out - everyone is shocked that a Primarch could be struck down. Big hoopla over it - and through his old connections and track record for victory, the Lion gets his wish and becomes the new Warmaster. Being a vindictive prick, he reorganizes the Legions loyal to him to rewarding positions, with much help and counsel by Luther and Lord Cypher.
Luther and Cypher have been covertly establishing connections with Legions who have already fallen to Chaos or are ripe for it and doing so in the Lion's name.
When the time comes, I believe it will be started by Magnus trying to warn the Emperor like in canon, and the Space Wolves being sent to punish them but things don't go as planned and the SW's take a serious beating from the pre-warned Thousand Sons fleet (courtesy of Luther or Cypher). Magnus and Leman Russ are both assumed dead in the intense fighting that sees heavy losses on both sides before the Thousand Sons withdraw into the Warp.
In the immediate aftermath of the Magnus Incident Konrad Curze confides in Fulgrim about his visions of the future and his myriad prophecies. In the wake of the events on Prospero this news is treated much the same - the Night Lords and Konrad Curze are summoned to stand trial and be judged by the remaining Primarchs.
The Night Lords turn and flee, firing on and destroying the Imperial Fists and Emperor's Children vessels sent to bring them to trial, retreating to Nostramo.
Learning the lesson of sending a single legion to bring another legion to trial, the Lion sends the massed strength of the Iron Hands, White Scars, Raven Guard, and Emperor's Children to bring the Night Lords to justice.
The first overt act of the Heresy would be several simultaneous attacks on multiple targets across the galaxy:
Ambush of the Loyalists over Nostramo by the Tzeentch-sworn members of the Emperor's Children in concert with a maddened assault by the Night Lords. The ambush does not go as well as hoped, and in retreat the EC unleash a psychic plague on the Loyalitst astropaths and navigators, killing or incapacitating all of them and temporarily stranding the White Scars, Raven Guard, and Iron Hands far from Terra. To further damage the stranded loyalists, the retreating Night Lords fire on the weak point in Nostramo's crust and cause it to explode, taking with it a number of Loyalist Marines who had occupied the world in the false belief that the Night Haunter was holed up there.
Brutal and ruthless surprise attacks on the Ultramarines by the World Eaters which keeps them from moving to relieve Terra. The Alpha Legion is busy helping the Ultramarines and cannot send serious support to Terra.
Sons of Horus leave their isolation of mourning and grief, emerging changed and blighted but at the same time strengthened, attacking the Salamanders and Nocturne, drawing them away from Earth into a long bloody stalemate.
Dark Angels arrive over Fenris, to the Lion's surprise as he has been temporarily confused/whatever by sorcery and when he returns to his senses, he is bombarded by reports of the widespread attacks and treason in his name. Furious at Luther, Cypher and the Dark Gods, he has no choice but to proceed. To signal his cooperation, he orders the Exterminatus of Fenris. He is joined by the forces of the Blood Angels, Iron Warriors, and Death Guard in his advance on Terra.
The Word Bearers, hearing of the betrayals by the forces sworn to the Lion, rush to Terra and join the Imperial Fists in preparing the defenses in the Sol System against the approaching forces of the Second Warmaster. There are clashes between the leadership styles of Rogal Dorn and Lorgar about how to defend the Sol System, but in the end, Lorgar accedes to the Emperor's Praetorian's defense plans.
When the Traitor Legions arrived in the Sol System, they were met by Loyalist space forces who attacked them as soon as they arrived, and but were forced to recreat as the superior weight of the Traitor Legions and the Lion's brilliant strategic skill made the battle bloody and one-sided. This came at the same time as the Fall of Mars to the Dark Mechanicum who declared their support for El'Jonson.
In this dark hour, the battle-scarred elements of the White Scars stranded at Nostramo arrived, having sacrificed their Librarians to guide their vessels through the Warp, at the cost of the sanity and lives of their Stormseers.
Loyalists fall back to Terra, and the defenses of Luna are smashed, along with the Loyalist fleet.
Traitors bombard and then land on Terra. Fighting ensues with the battle stalling out to a siege of the Imperial Palace, with the Fists and Word Bearers holding the walls while the White Scars to hit-and-fade missions to stall out any advances.
Iron Warriors & Blood Angels attack and attempt to breach the Eternity Gate but are held by Lorgar who stands alone against the assault, until while locked in combat w/ Sanguinius, he is stabbed in the back by Perturabo.
However, this victory is overshadowed by word that the Alpha Legion and Ultramarines have broken through and scattered the World Eaters and are driving on Terra. Even the battle-scarred and decimated Space Wolves have reached the stranded Iron Hands and Raven Guard and will see them arrive shortly after the AL & Smurfs.
Being less of a gambler than Horus, the Lion uses Sorcery/Warp mumbo-jumbo to lure the Emperor, Rogal Dorn to his Flagship only to find the Lion isn't present and its a trap - the warp drives are tainted and explode in waves of dark energy that kills or corrupts more than half of the forces on board. Dorn is spared, but the Emperor is horribly maimed. Dorn grabs the comatose Deity-Sovereign and bugs out while the ship comes apart.
El'Jonson knows his trick failed to kill the Emperor and orders his Dark Angels to disengage over the objections of Luther. His forces initiate a surprise fighting retreat, keeping the overwhelming majority of his forces intact. The Blood Angels and Iron Warriors on the other hand, take heavy casualties during the surprise retreat. This ensures that though the Lion lives, none of the other traitor legions will ever trust him again.
The Emperor & Dorn land on Terra and the crippled Emperor tells Dorn that he is physically crippled and how to make the Golden Throne a life-support system to keep him alive and tie his mind into the Astronomicon. Though he lives, the Emperor can no longer lead the Imperium or even communicate with his Sons. He is forced to spend the majority of his focus, power, and effort to keep himself alive and his warp-tainted injuries from killing him. The Emperor has the theoretical ability to communicate and interact, but between the Chaos attack, the failure of his primarchs, and the degeneration of the Imperium into everything he was fighting against he doesn't except in very extreme situations. Instead of just the Astronomicon needing regular infusions of pyskers to work, the Imperium instead sacrifices a horrifying number of psykers to boost the Emperor's strength long enough for him to tell them how to handle a particularly horrifying event - like the Tyranids or such. Any interaction with the Emperor is very brief, cryptic, and confusing - not to mention dangerous to the Emperor who must take a fraction of his attention from his injuries, and to whoever by necessity must be present in the Throne Room when such absolutely titanic psychic energies are unleashed.
LOYALISTS
The Penitent Sons (a major pain to write this up in a clear manner)
When the majority of his legion turned Traitor, Fulgrim was left stranded with a small core contingent of Loyalists as the Traitors led by Fabius Bile looted the Legion armories and seized or destroyed all of the Legion's accompanying ships. After the Heresy, Fulgrim and his loyalists were recovered from their brief exile and placed on trial by the surviving Primarchs. Only Ferrus Manus' intercession prevents the complete disbandment of the Legion but they punishment they receive instead is far harsher - the Loyalists are stripped of the right to wear the aquila or indeed any insignia and are forced to perform exterminatus on Chemos and undertake a crusade for penance. While on this crusade, the Emperor's Children would be banned from taking new recruits for 100 years. After leaving the ashes of Chemos behind them in a few salvaged ships, the loyal Emperor's Children changed their name to the Penitent Sons as a sign of their great guilt.
To prove their devotion to the Imperium and atone for their past failures, the Penitent Sons perform regular ritual scarification of their faces while having their oaths of service tattooed into the flesh of their chests. As the tattoos and scars fade, they are re-applied so that the symbols of their dedication never wane.
Doctrinally, the Sons have abandoned their past quest for perfection and become ultra-specialized, and in their quest for redemption of their predecessors' sins the sons of Fulgrim seek release in close combat bringing death to the enemies of the Emperor with bolt pistol and chainsword. Many, if not most, battle brothers have a death wish of various strength and eagerly seek out battle without fear or hesitation.
The loyal survivors of the Third Legion embraced the Codex Astartes proposed by Roboute Guilliman with a fanaticism that is unmatched. The only deviation initially allowed by Fulgrim and his fellows is a total ban on psykers within the legion as warpcraft had brought about their downfall once before. Over time, necessity has forced them to modify their adherence to the Codex as the Penitent Sons suffered combat losses they were unable to replace. At the end of their 100 year ban on recruiting, the Sons were forced to accept both Inquisitorial and Nightwatch approval for any new recruits. This laborious process ensured that the Penitent Sons could not replace their numbers as fast as they lost them.
The attrition of the constant campaign and self-castigation would have meant the end of the sons of Fulgrim if not for their actions in M36 that brought a swift and sudden end to the Age of Apostasy. The forces of the Renegade Bishop Bucharis had been driven back to their capital on the planet Gathalamor but the end would not come quickly as the renegade naval vessels loyal to the Cardinal formed a defensive cordon around the world and repelled repeated attempts to force a breach and land troops. The stalemate remained in place until the sudden arrival of the Penitent Sons who had been reduced to only 400 astartes and a single battle barge the Lash of Punishment.
Without warning or indecision the Lash dove through the renegade naval vesses, ignoring the weight of their fire to emerge over the Cardinal Palace and unleash the entire complement of the Penitent Sons in drop pods regardless of the consequences, even as their void shields fell and the mighty battle barge exploded.
The ensuing battle to take the Palace would be one of the most costly and important for the Penitent Sons since their betrayal during the Heresy with barely half of Astartes living to see the fall of the Palace and the end of Bucharis' rule. The sacrifice of the Sons was noticed by the powers of the Imperium, and for their actions the sons of Fulgrim were granted permission to recruit initiates for rebuilding and to eventually establish successor chapters.
Even after centuries and even millenia of crusading their loyalties remain suspect by the Imperium at large which has seriously affected their equipment - their Terminator armor, confiscated during their trial after the Heresy, has never been returned. The Penitent Sons have remained the least likely Chapter to receive new or repaired equipment and vehicles. With few vehicles left those that they have remaining are only sent into battle in dire need. The Sons have at best three Land Raiders left for all their forces and Rhinos are almost as rare with no new vehicles, such as Razorbacks, to replace them.
With the severity of his punishment and the magnitude of his failure, Fulgrim sought to emulate the demeanor of his closest brother's Iron Hands Legion. This has led to the Penitent Sons exhibiting a demeanor of curious mixture of conservatism, fatalism, and brutality that became the foundation of their reputation among Imperial units as the most brutal Astartes Chapter.
Though Fulgrim physically survived the Heresy, it could be argued that his spirit did not - in the years and centuries to follow he lapsed into an ever deeper spiral of depression, self-loathing, and self-pity whereupon he would spend hours and eventually days punishing himself in the embrace of a pain glove. The end would finally come for the broken Primarch during the Great Scouring in a battle to take a damaged Strike Cruiser belonging to the Blood Angels attempting to reach sanctuary in the Eye of Terror. During the course of the battle, one of the Traitor Astartes struck down the Primarch with a daemonic blade from behind. Even with the death of their Primarch, the Penitent Sons pushed forward and eventually purged the vessel of all foes before destroying the ship with demolition charges.
Primarch - Fulgrim - dead shortly after the Heresy.
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Space Wolves
The Sons of Russ only barely resemble any adherence to the Codex after the disappearance of Leman Russ on Prospero while locked in mortal combat with the Traitor Primarch Magnus the Red. The loss of Russ would only be surpassed by the destruction of Fenris by the traitors of the Dark Angels.
After the Heresy, the Space Wolves have become a scattered Legion divided further into successor Chapters with many Great Companies operating completely independently of their chapter hierarchy.
Even without Fenris, the Space Wolves still want to keep inducting blooded killers into their ranks so they start going for the most concentrated collection of killers possible - the Imperial Prisons. With great intent the Astartes begin beating their Fenrisian culture and heritage into the heavily tattooed prison scum that make up their recruits. Their new recruits have lead the Wolves to become even more savage and barbaric in battle than before, approaching the infamous brutality of the Pre-Heresy World Eaters.
Primarch - Leman Russ - Believed alive but lost in the Warp, possibly locked in eternal battle with Magnus the Red.
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The Faithful
Following Lorgar's death in the defense of Terra the surviving Word Bearers become similar to a cross between the Doom Eagles, Black Templar, and Mortifactors. The death of their Primarch and the crippling of the Emperor will make them go crazy and they're going to go on constant attacks on the retreating traitors regardless of the losses. They draw out the more fanatical and religious elements of the other Loyalist Legions like the predecessors to the Doom Eagles, Black Templar, and Mortifactors to join them and the combined force takes up the name the Faithful.
This lets the surviving legions purify themselves of superstition and let the fanatics reduce their own numbers while hurting the enemy. This works by the end with the Faithful being much reduced in number but has the unwanted side effect of making Emperor Worship universally widespread and the official and enforced State Religion of the Imperium.
Dorn and Guilliman had no problem offloading their problems to die honorably while removing a potentially serious threat to the stability of the Imperium. They don't see the inevitable gene-seed degeneration in the Word Bearers as such because they instead see it as injecting some higher quality elements to Lorgar's ignorant genetic soup. The end result is a nice twist on the usual Black Rage - like Dorn's successors, their sus-an membrane doesn't work, so they can't go into suspended animation and a mutation in the Preomnor implant alters the neuro chemical balance of the brain over time that results in a steadily increasing focus and perception of time and space which causes their reflexes to become steadily faster until they give the impression of mild precognition. This comes at the progressive loss of self as a marine becomes nothing more than a living combat weapon who eventually will not care for themselves at all - they won't eat, drink, treat their own wounds, sleep, talk and at the deepest levels they will completely stop breathing and simply die. The only way to keep them functional in the latter stages is their intense hypno-doctrination and ingrained combat training and muscle-memory. The Astartes of the Faithful call it "the Sorrow".
The large numbers of Marines succumbing to the Sorrow has lead the Faithful to field large numbers of Dreadnoughts in lieu of vehicular support, but these dreadnoughts differ from their kin in that that they need the guidance of a chaplain to remain in control and be directed on the battlefield - without that constant guidance they will set out on their own to attack the nearest enemy on the battlefield with no organization or control.
Primarch - Lorgar - killed by Perturabo on Terra
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Raven Guard
In this alternate heresy the Raven Guard were not decimated at Istvaan-equivalent, which means that they were fully engaged in the post-Heresy pacification of the Imperium. This means that while some of their stealthy/guerilla doctrines are still around, they might have had to resort to more straightforward tactics. Their covert warfare experience made them more adept at infiltrating fortifications and taking them, giving them much different skill set in the long run. Additionally, it gives them much more merciless attitude, which eventually leads Corax to leaving for the Eye of Terror, ostensibly on a mission of revenge, but really because he saw he was becoming just like the people of Lycaeus/Kiavahr before he showed up (which means he will be missing, presumed dead).
As a result, the Raven Guard are much closer to the canon Imperial Fists or Dark Angels, and while some minor mutations exist in their gene-stock, they are considered to have one of the better, more dependable lines of gene-seed. They are also the Chapter/Legion of choice to call upon when fighting insurrection, and, while relatively humanitarian outside of war, they can be utterly relentless and brutal in war, to where anything goes for accomplishing victory. This would lead some Imperial Army regiments to refuse to fight alongside the Raven Guard, who wouldn't think twice about sacrificing their erstwhile allies if the need calls for it.
The needs of suppressing the post-Heresy rebellions causes them to adopt more Terminator squads, and take a somewhat non-Codex organization, in that they will be less specialized as a Chapter, but more specialized on Company level. They would have dedicated "guerrilla war" companies, dedicated "heavy assault" - read Terminator - companies, dedicated "fast attack" companies - completely composed of Assault Marines and bikes, etc. The idea is that a Raven Guard force has many different Troops choices and army configurations available to them, but the actual army structure is heavily dependent upon which doctrine they choose at the onset of battle, perhaps through the HQ character they deploy.
This way, a Raven Guard army could play similar to Dark Angels Deathwing, they could play somewhat similar to canon Blood Angels (with Assault Marines taken as Troops, and supported by bikes, which is a Raven Guard difference from Blood Angels), or they could take an all-scout force (unique to Raven Guard). The drawback is that this doctrine is VERY specialized, and generally has severe limitations; while they can put together a basic, all-around force, they will do so at the cost of being unable to include special HQ characters, having to make do with a very generic Captain or some such.
Primarch - Corax - missing, presumed dead
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White Scars
The White Scars are a lot like the canon Space Wolves, albeit with a few successors (due to reasonably decent gene-seed), and perhaps little more pliable to the Codex than the Wolves. Still bike-mounted, with perhaps Ravenwing-like formation (which can be accomplished with canon White Scars as well), but also focus on Land Speeders and the like, with a unique unit that is basically a jump-pack Devastator squad (i.e. heavy firepower and mobility, disdain for close combat).
Primarch - Jaghatai Khan - Unknown location
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The Salamanders
The Nurgle-infested Sons of Horus are sent to attack Nocturne while the Salamanders are away in the first hours of the Heresy. This would basically exterminate most of Nocturne's population, and force the Salamanders to kill the rest of their people when they return to expel the SoH.
Killing plague zombies that were your charges until now has resulted in a very, very grim Chapter.
The Salamanders have a massive guilt complex, and would take their humanitarian streak to even higher extremes. While they would attempt to repupolate Nocturne, they would turn it into a "refuge planet", which, in turn, would mean they will accept people not wanted anywhere else in the Imperium - psykers, some types of mutants, refugees from many of the Imperium's wars...
The Salamanders would end up running a small empire centered on rebuilt Nocturne (and having anywhere from 5 to 10 systems), which will be arguably a nicer place than most of the Imperium, but not without its price. The lack of genetic conformity in their recruiting population, high levels of radiation on Nocturne, and the need to rebuild after the Heresy might have resulted in some degradation of their gene-seed that has seen some increased functionality in certain implants and mildly decreased functionality in others.
Because of their degrading gene-seed and accidental empire-building, the Salamanders are somewhat distrusted, and there are very few Chapters made with Vulkan's gene-seed. The general Imperial consensus is that the Salamanders serve a useful purpose with the Realm Of Fire (i.e. TTL's Ultramar) and have proven loyal, but are very close to the line of what is acceptable (in how they actually dare to treat their subjects WELL), and therefore should not be made any more powerful.
Primarch - Vulkan - disappeared with his First Company Veterans into the Eye of Terror pursuing the Sons of Horus during the Scouring.
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The Imperial Fists
After the Heresy, the Imperial Fists became divided between three conflicting visions - that of the Faithful who attracted the more religious members of Dorn's Legion such as Sigismund the Emperor's Champion, that of Guilliman and his Codex Astartes, and that of Dorn. Most of the legion stayed loyal to Dorn's vision and followed him on a mission to drive the Iron Warriors from their fortress on Sebastus IV in the Iron Cage incident where Dorn's arch nemesis Perturabo outsmarted the architect of the Imperial Palace. In the bloody ambush on the planet's surface the Fists held out for days cut off from supplies or support, even after the death of Rogal Dorn in a failed counterattack. It appeared that Dorn and his most loyal Astartes were to die there until the arrival of the members of the Imperial Fists who had split away from the Legion to follow Guilliman's Codex.
With their primarch dead and their numbers dangerously low, the Imperial Fists were desperate to regain their lost honor and return to the service of the Emperor. In their haste the Fists used dangerous and careless methods to produce gene-seed faster and mature recruits with record speed - in the end the shortcuts rendered as many as five different implants non-functional with other organs threatened with failure. Faced with the threat of total collapse, the Fists appealed to their brothers in the Guilliman-inspired successor chapters for donations of their gene-seed to prevent further degradation and mutation. This arrangement has left the Imperial Fists constantly under strength and resentful of the Codex Successor who in turn resent the Fists for their failure in the Iron Cage Incident and for the steady loss of Gene Seed. It is something of an open secret that the Inquisition only tolerates the Fists degradation because of their status as a Found Legion.
With their weakened condition, Imperial Fists doctrine has placed ever greater emphasis on ranged firepower and the avoidance of close combat wherever possible.
Primarch - Rogal Dorn - killed in the Iron Cage incident
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Ultramarines
The only change is less insistence on the Codex organization, making the Codex a suggestion rather than an order for the most part. Certain things would still be enforced (i.e. keeping the Chapters at roughly 1,000 men, although there will be several exceptions, such as the Faithful - initially at least, until constant attrition depletes Lorgar's lot to more manageable levels), but some other things, such as tactical doctrines, might be a bit more flexible.
I would see the Ultramarines as being fairly similar to canon, although they would have had LESS influence on the Imperium at large due to stronger, more organized opposition to Guilliman.
Though Alpharius would be the first High Lord of Terra, Guilliman would serve as the Lord Commander of the Imperium's Armed Force. Guilliman's proposed Codex Astartes would find limited acceptance by his fellow primarchs whose organized resistance to the Codex's strict principles forced a compromise whereupon the Codex has become a guideline to follow and not a binding ironclad document. As such there are few strictly codex chapters, the most notable being the Ultramarines themselves, and the successor chapters of the Imperial Fists being the other most notables.
After the end of Alpharius' term as High Lord of Terra and subsequent disappearance Guilliman became the new High Lord of Terra. The Primarch of the Thirteenth Legion would have a very short reign as High Lord before being assassinated by a Chaos-tainted Callidus Assassin, and his dying body enthroned in a stasis field on Terra.
After the death of Guilliman, the position and authority of the High Lord of Terra was dispersed among several positions so as to prevent a single individual having absolute power over all organs of the Imperial government - though the High Lords are forced to meet in the presence of the enthroned Primarch, who is said to see all and hear all said by the High Lords. Just prior to the Age of Apostasy, a High Lord known for his greed and corruption mocked the fallen Master of Macragge, calling him the "Emperor's representative". That night, the High Lord was found in his chambers murdered in a most horrible fashion, and his many material possessions destroyed. At the next meeting of the High Lords, the disrespectful Lord's tongue was delivered by an ancient servitor, skewered on a gold spike in the shape of an Omega. After this event, the High Lords of Terra assiduously avoid any implication of corruption or disrespect.
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Iron Hands & the Adeptus Mechanicus
The Fall of Mars to the Traitors during the Heresy was a great loss to the Loyalists in the build up to the Siege of Terra. After the retreat of the Traitor Legions, it fell to the Iron Hands to "liberate" Mars from the Chaos-tainted Dark Mechanicus.
The swift fall of Mars and the generally good state of its infrastructure found during its recovery lead to a considerably amount of resentment, suspicion and outright anger by the Loyalists in regards to the Adeptus Mechanicus as a whole.
To repair the damage done to the Red Planet during its occupation and to "restore everything to its proper place" High Lord of Terra Alpharius and Lord Commander Guilliman agreed to name Ferrus Manus as the Regent and Interim Administrator of Mars. The move was exactly as it appeared to be - a symbol that the Primarchs believed they could not trust the Adeptus Mechanicus.
This act almost brought about another crisis as the Forge Worlds and domains of the Mechanicus across the Galaxy that had remained loyal during the Heresy threatened to secede with such a clear breach of trust and a violation of the Treaty of Mars. To prevent an outbreak of civil war so soon after the events of the Heresy, Alpharius brokered a deal - the Mechanicum on Mars would remain under the authority of Terra and its appointed Regent for 100 years before returning to its own administration. As a result the Mechanicus would gain more independence, a greater role in the Imperial military affairs, and two representatives among the High Lords instead of one - one from Mars, and one from the other conglomerates of worlds that are NOT directly controlled by Mars.
This agreement placated the non-Martian Mechanicus and over time has lead to a de facto division within the Adeptus that has carried on even after the departure of Ferrus Manus from his role as Regent - the Martian Mechanicus, which remains closely tied to Terra, and and the non-Martian Mechanicus, which pays lip service to Mars, but, due to the above agreement, acts with far more independence. In fact, there are entire sectors of the galaxy that are given to this Mechanicus to govern, which makes them more or less a no-go territory for the uninvited (i.e. other Imperial organizations, with very few exceptions).
This division has lead to a mild schism within the production qualities of the two factions - the Martian splinter remains very traditional but supremely efficient, producing everything from bayonets to bolters for the Imperial Army and the Astartes with no deviation from established patterns. The independent Mechanicus-realms on the other hand are known to produce small quantities of unique or improved equipment in exchange for a variety of services or needs on the behalf of friendly Imperial Army regiments and Astartes Chapters. This friendliness comes at the price of cooperation with the Martian Adepts, who are well known to punish those friendly units with very slow equipment deliveries and "accidental" logistical errors.
The Adeptus Mechanicus were not the only organization to emerge changed from Ferrus Manus' tenure as the Regent of Mars. During his time as the Interim Administrator he freely "borrowed" designs and equipment from the Mechanicus stores and knowledge to enrich his own Legion. His Astartes became equipped with the newest patterns of armor, bolters and vehicles while their doctrines shifted to include massed formations of armor supported by copied designs from the Legio Cybernetica. These copies of the Martian combat robots march to war side by side with the ranks of tanks, dreadnoughts, and artillery now favored by the 10th Legion during battle.
Their good fortune with their re-equipping and re-training after their time on Mars has seen the diminishing of their more ruthless and unforgiving aspects and the rise of a somewhat noble character, though the Iron Hands remain above all else, Astartes.
Some time after leaving Mars, Ferrus Manus disappeared from the known galaxy. Many rumors insist that the Primarch has returned once more to Mars where he resides in secret, but the Martian branch of the Mechanicus and the Iron Hands both deny these rumors.
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Alpha Legion, The Holy Inquisition, and Nightwatch
After the events of the Heresy, and the crippling of the Emperor, Alpharius, Primarch of the Alpha Legion became the temporary High Lord of Terra and political leader of the Imperium by the agreement of the surviving loyal Primarchs and the mortal leadership of the various branches of the Imperium. Alpharius was selected as a compromise candidate with no strong connections among the Primarchs save for the deceased Horus. Alpharius was also the candidate favored by the Primarchs opposed to Guilliman's proposed reorganization of the Legions into regimented Codex Chapters - Guilliman himself did not oppose the move, as the two former rivals had largely closed the rift between them during the events of the Heresy. As High Lord Alpharius opposed the stricter elements of the Codex Astartes but supported the separation of the Legions into thousand strong Chapters. The large numbers of the Alpha Legion and Ultramarines has lead to each accounting for a third of all successor chapters with the other loyalist legions making up the remaining third.
During his temporary appointment as the High Lord, Alpharius was instrumental in the establishment of the shadowy secular organization known as Nightwatch, which concerned itself many covert operations across the Imperium, mostly focusing on Xenos, and the Traitor Legions while only barely dealing with the issues of mutation, small-scale treason, or religious heresy.
The Nightwatch's lack of outright piety and support in suppressing religious dissent eventually leads the Ecclesiarchy to establish the Holy Inquisition with the support of enemies of Nightwatch who resent its power in the Imperium's armed forces. The Inquisition is a ruthless, brutal and religiously organ but has sole focus on mutants, heretics, small-scale treason, and fighting daemons with the Nightwatch energetically maintaining its own jurisdiction which the Inquisition reciprocates. Something of a shadow war constantly takes place between the two organizations as they vie for power in the Imperium and seek to undermine the other while carrying out their mandated missions to protect the Imperium at the same time.
Despite claims to the contrary, the Holy Inquisition doesn't have the supreme authority of life and death over all of Humanity, they wield a great deal of power (which is matched by that of Nightwatch). With a long history of non-cooperation from outsiders, the Inquisition has their own armed forces made of up of Frateris Militias, Frateris and Sororitas Templar, Death Cult Assassins, Eversor assassins, and the very secret Grey Knights Astartes Chapter. The Inquisition is NOT subtle or forgiving, is very dogmatic and doesn't allow for much free thought.
Nightwatch on the other hand has fewer dedicated troops, instead recruiting volunteers from Imperial Guard and Astartes. The organization does maintain full-time agents, Callidus assassins, Vindicare assassins, and the specialized anti-psyker Pariah Marines. Compared to the Inquisition, Nightwatch and its members are subtle, manipulative, and shadowy, but allowed a surprising amount of room for free thinking and innovation - rumors among the Inquisition maintain that Nightwatch is the main organ for advancing Imperial technology by stealing and dissecting heretical Xenos tech.
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Imperial Army
Following the events of the Heresy changes were made to the structure of the Imperial armed forces. Many of these changes were made to ensure that no single individual would be powerful enough to ever again to attempt to overthrow the ruling body of Imperium if he turned traitor. To this end the existing Imperial Army was divided between the Imperial Army which is responsible for the Imperium's ground forces and the Imperial Navy which is responsible for the fleets of warships that travel between the worlds of the Imperium.
TRAITORS
Mechanicus influenced Iron Warriors FTW. Cold, emotionless, calculating but still Chaos. Go into combat with combat servitors, arco-flagellants, eversor cyborgs, and even a few Penitent Engines leading the way to soak up fire and casualties or to man the siege works and fortress walls.
Primarch - Perturabo - Injured on Terra, he has since become infused with the Obliterator virus and become a massively powerful fusion of man, machine and daemon. Some sects of the Adeptus Mechanicus secretly worship him as an avatar of the Omnissiah.
Leadership – Perturabo retains leadership of the Iron Warriors overall but very rarely takes to the field of battle, instead leaving his Warsmiths largely independent and in charge of their own Grand Companies.
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The Black Legion of Psykers for Thousand Sons is a good description – in the aftermath of the destruction of Prospero the Thousand Sons have emerged across the galaxy to rescue oppressed psykers from Imperial oppression, even going so far as to organize raids on Inquisitorial Black Ships. Secretly the Thousand Sons are consuming the psychic powers and potential of their freed Psyker recruits to keep themselves stable and generally mutation free. This psychic vampirism would come with the added bonus of getting a brief boost to their powers. I could see them keeping psyker-slaves nearby in battle for a quick pick-me-up and even turning on the weaker members of their warband in very desperate times. They'd be mildly associated with the Dark Powers, but leery of their influence.
Primarch - Magnus died on Prospero, possibly at the hands of Leman Russ who may have died in the ensuing pandemonium.
Leadership – the Thousand Sons were swept into the Warp by the forces unleashed during Magnus’ suspected death and largely scattered. The largest and most cohesive survivors of the Thousand Sons are lead by Ahzek Ahriman and a handful of surviving fellow captains.
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Mortarion decides that the only reason he failed on the mountain top and the Emperor succeeded is that the Emperor had superior technology and used it to its full advantage – so Mortarion instills this idea into his Death Guard that his foot slogging infantry should be armed and armored with the very best equipment available.
For the Tech obsessed Death Guard, I'm thinking lots of Combi-Weapons, customized power armor, plasma pistols and power swords preferred over bolt pistols and chainswords and heavily armed Terminators everywhere for support (IIRC the DG had the most Terminators of any legion) backing up the very versatile DG squads which would including a heavy weapon. For added protection, there would probably be lots of Chaos Warding on their armor and daemonic infusion into everything they have.
Primarch – Alive and active. After the withdrawal from Terra, Mortarion has left his legion on his own quest at the behest of the Dark Powers. His quest has him return at seemingly random intervals to lead his legion in attacks on seemingly worthless or random dead worlds across the Galaxy. Mortarion has also been seen to lead his legion into temporary alliances of convenience with the Dark Eldar to create and stockpile special weapons of a psychic nature for use against mutual foes of the “most ancient and dangerous kind”. Such alliances always end with mutual betrayals and bloodshed at the end of which Mortarion and his Deathshroud bodyguards disappear with whatever new weapons they manufactured with the Dark Eldar.
Leadership: During his long periods of absence, Mortarion has named First Captain Calas Typhon to serve as the leader of the Death Guard until his return.
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The Blood Angels path to corruption and worship of Slaanesh began with Sanguinus rescue and early years on Baal Secundus battling horribly disfigured mutants. This period of time instilled in Sanguinus a loathing of the disfigured mutants and their corruption of the beauty and perfection of the human form. Once elevated to command of the Ninth Legion, Sanguinus passes on this loathing of mutation and human imperfection to his Astartes.
Over time, Sanguinius and his Astartes start to feel unappreciated for all their hard work killing ugliness and imperfection in the galaxy, and the whispers of the Lord of Dark Delights took root, offering great rewards for their dedication.
Once dedicated to the Prince of Pleasure, the favored of the Legion have wings like Sanguinus, though theirs are gifts from Slaanesh. The Blood Angels still strongly favor assault tactics at close range, and to further gift his chosen warriors, Slaanesh has gifted them with a powerful glamor the confuses their foes, and slows their reactions.
Primarch - Sanguinus is alive and active.
Leadership - despite Sanguinius' survival, the Blood Angels are divided into warbands roughly along the lines of Great Companies that rarely cooperate without the direct order of the Blood Angel.
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The Sons of Horus who worship Nurgle after the death of Horus in a long dark despairing depression. Hate and resent everyone else for not protecting or appreciating the fallen Warmaster. The SoH vehicles have all become possessed by daemons, freeing even more Astartes for the battlefield. Like their vehicles, a lot of the SoH are possessed by Plaguebearers, getting a long scythe-like mutant limb for close combat and spreading disease while also producing clouds of flies and bits of foul nastiness that conceal their brethren as they advance across the battlefield.
Primarch - Horus is dead, struck down by the powers of Chaos when he would not convert.
Leadership - after the death of Horus, Maloghurst the Twisted has assumed control of the Legion with the aid of Erebus, the Legion's great religious adviser who guided them after Horus died into the worship of Nurgle. Individual Grand Companies/Warbands swear fealty to Maloghurst.
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The Emperor's Children breakaways lead by Fabius Bile would account for a rather large number of the Legion and would dedicate themselves to Tzeentch on the quest of seeking perfection through mutation, gene-engineering, tissue grafts, and combat drugs. Each member of the EC would gain a powerful Wild Talent that is powerful but hard to control, with failure resulting in severe mutation, madness, or devolving into Chaos Spawn.
Primarch - Fulgrim remained loyal to the Emperor
Leadership - Though Bile is officially in charge of the Legion, he rarely concerns himself regular operations, instead preferring to remain his laboratories and conduct his vile experiments. Warbands are commanded by champions of Tzeentch, drawn from the ranks of fallen Lord Commanders.
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The Night Lords would be torn apart in Civil War when a renegade Night Haunter is driven mad by conflicting visions of the future. Each company and warband of the NL would seek to prevent or ensure the fulfillment of a different prophecy inked by the Haunter before his death. Due to a mildly more noble streak in his character, the Haunter is not a Fear-mongering Terror Junkie but instead a draconian tyrant obsessed with his visions of the future. His Legion has a serious Cassandra Complex and blurs the lines of insanity with random attacks on sometimes totally worthless targets. At the scene of every attack they leave fragments of the Haunter Prophecy their warband/company is working on.
In addition to a toned down skull-and-bat motif of canon, each member of a warband covers his armor in complex Nostroman glyphs telling parts of the Prophecy their warband is dedicated to.
Primarch - Konrad Curze is dead, killed by own Legion.
Leadership - fragmented into warbands of varying sizes.
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The World Eaters instead of going all skulls-and-blood berzerker crazy have a calm, controlled, collected and calculating leadership. Perhaps some of the captains thought Angron was a little too nuts and allowed their lower-level marines to get skull implants while avoiding them personally. During and after the Heresy they herd Angron and his berzerkers into combat while executing their own attacks with the mindless berzerkers soaking up the fire and taking the losses. Over time, the losses in lower level marines and their very short battlefield life expectancies has lead to the leadership cutting corners in recruiting - they use recruits other legions wouldn't use for target practice implanted with badly degraded gene seed and failing clone organs that will fail within a few short years (a result of accelerated gene-seed growth processes and gene seed alterations) but grant the recruits unnatural strength and resistance to harm. The deficiencies in recruits and gene-seed is further offset with the fitting of new-model cranial implants that are inactive until battle is imminent to keep the berzerker-fodder docile while driving the warriors into ever greater rages. Whenever possible, the disposable berzerkers are equipped with the recovered arms and armor of their fallen predecessors and dead foes that has been hastily repaired. Eventually Angron proves to be too great a danger for his clear-thinking captains who can't risk losing him on the battlefield so the Primarch is subdued and lobotomized, trapped as an insensate vegetable for eternity and constantly harvested for genetic material to replace worn-out Gene Seed.
Primarch - Angron is a vegetable constantly harvested for Gene Seed.
Leadership - the Legion is now in the hands of the Captains present after the Primarch's recovery, but as a first among equals, Kharn the Betrayer speaks with the most authority. Kharn earned that moniker as the mastermind behind Angrons brain-panning, which he undertook without the agreement of his fellow captains. He is feared, loathed, respected, and admired in equal measure.