The Roboutian Heresy

by Zahariel

Inspired by the great Dornian Heresy of Aurelius Rex, here is an alternate timeline to the Warhammer 40000 universe, where Guilliman turned traitor instead of Horus, and led half the Legions in rebellion against the Emperor. The Index Astartes are done for all Legions. Now, the Times of Ending have begun ... Also has a TV Tropes page now !

7. Index Astartes : Imperial Fists

I do not own the Warhammer 40000 universe nor any of its characters. They belong to Games Workshop.

Inspired by the Dornian Heresy, by Aurelius Rex.

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Index Astartes – Imperial Fists : Knights of Blood and Blades

Few Traitor Legions have fallen as far as the Imperial Fists, whose name echoes bitterly through History accompanied with the laughter of the Blood God. Once they fought at the forefront of the Emperor's armies, bringing worlds under His aegis with cold fury and unmatched discipline, carrying high the banner of the Imperium's dominion. But now they are warriors, not soldiers. The sons of the Seventh Legion lost all unity in the flames of failure and betrayal, and are now a Legion in name only, scattered across the Eye to do the bidding of their Dark God in return for its protection – the only thing preventing them from falling into the madness that burns within their Primarch's soul ...

Origins

Ten thousand years ago, the Emperor of Mankind rose from the darkness of the Age of Strife to bring a new light to a galaxy shrouded in shadows. After uniting Terra behind Him and claiming the lore of the Dark Age of Technology as His own, He prepared a grand plan to free the galaxy from the chains of xenos menace and superstition. One of His tools was the secular Imperial Truth, a message of illumination that was to be spread across the stars. The second, and perhaps even greater, was the Primarchs : twenty beings of unmatched power, born of humanity and the Emperor's own blood. They were to be the generals of His Great Crusade, the leaders of the armies He would create in their images. But there were entities that had other ideas.

Before the Emperor's work reached completion, the Ruinous Powers, also known as the Primordial Annihilator or, more commonly, the Dark Gods, stole away His twenty sons and scattered them across the galaxy. By accident or design, all of them ended up on worlds populated by human beings, and all of them, in one way or another, rose to their individual greatness until their father found them again – but none more so than Rogal Dorn. Where his brothers conquered their homeworlds, he rose to become the sovereign of an entire cluster of planets.

The Seventh Primarch was found on the ice-world of Inwit. Despite its difficult conditions, that planet was home to a sizable human population. Centuries ago, the people of Inwit had rediscovered the technology needed to travel between worlds, and had built a system-spanning kingdom. Yet while they possessed space ships and limited Warp travel, those who lived on Inwit itself had kept to their tribal ways, forming ice clans that hunted the many beasts of the world. In doing so, they believed that they could preserve the strength of their spirit, instead of growing soft by embracing the comforts of civilization.

Little is known of the early infancy of the Imperial Fists' gene-sire. He was found and adopted by the House of Dorn, greatest clan of Inwit. Like many other Primarchs, his unmatched genius and martial ability drew the attention of the mighty, and he was chosen by the Patriarch of the House as his heir. What few accounts remain available of that period when Dorn ruled the Inwit Cluster describe it as a time of great peace and prosperity, with several more worlds being discovered and added to the coalition by Dorn's exploration teams. Had the Emperor found His son then, no doubt Inwit would have become a jewel of the Imperium. But the first to find the cluster of worlds were not the vessels of the Master of Mankind, but the ramshackle Roks of the greenskins.

From the edge of the Inwit Cluster came hundreds and hundreds of Ork tribes, intent on plundering the riches of the human worlds. This was no Waaagh ! led by a single Warboss, but a gathering of dozens of lesser groups, drawn together by the unfathomable whims that control the Orks' sorry excuse for a mind. Seeing this threat to his domain, Dorn gathered his forces and raised a great fleet and army with which to meet the xenos. At first, the war went well : the Orks were no match for Dorn's tactical insight and their fury couldn't hope to resist the hard discipline of Inwit's defenders. But as the battles went on, other Ork tribes were drawn to the promise of a good fight. At the time, the Great Crusade was not yet fully going on, and there were still immense empires of greenskins polluting the stars, led by alien tyrants of such might as had rarely been seen since. The Inwit Cluster was near – galactically speaking – several of them, and their Overlords, upon hearing of the giant in yellow armor who led the humans against them with such efficiency, began to move toward the source of the tales.

The Phalanx
Before the Emperor found His seventh son on Inwit, Rogal Dorn found the ruin of what would become the flagship of his stellar kingdom. Forged during the Dark Age of Technology, the ship was orbiting Inwit, wrecked by damage so grand that none then could guess what had been the cause. Dorn restored it and enhanced it, gaining a fortress in space possessing more firepower than an entire fleet of lesser vessels. He installed his government aboard the ship, traveling from world to world to ensure the Inwit Cluster's unity and prosperity as well as hunting pirates and xenos raiders. When the first elements of the Waaaaagh ! arrived into the Inwit Cluster, Dorn brought the Phalanx to battle and defeated them with ease.
The ship was lost in battle against seven Space Hulks, destroying all of them but taking fatal damage in the process. Dorn himself was on board, directing it until its final moments, but his crew forced him to evacuate, telling him that his life was needed to protect Inwit from the rest of the Orks.

The war against the Orks lasted for years, and Dorn grew more and more somber as the military campaign went on. The loss of his flagship, the Phalanx, in battle against several Space Hulks gathered by the Waaaagh ! hit him most harshly of all. Not only had the vessel been the political heart of his kingdom, it had also been the repository of many of the Primarch's childhood relics, mementos from his foster family now long dead. If one were to attempt to identify when the soul of Rogal Dorn was first touched by darkness, one could probably point at that moment – though many other Primarchs suffered similar losses, and remained pure.

The pod was drifting in the darkness of space, alone and ignored by the behemoths that waged war against each other in the infinite black. Dorn watched the last moments of the conflict through the pod's sensor array, seeing his flagship burn through columns of numbers and red dots. The Phalanx had been his home for more than fifty years. It had been the seat of his kingdom, but more than that, it had been the one place where he had truly felt at peace. And now it was gone, and his most loyal servants were gone with it. He himself would survive, he knew that. Though he had never seen it before that day – in truth, he had not even known it existed – Dorn didn't doubt that his people had outfitted it with the best tech available, to ensure that he would survive even if the unthinkable was to happen. He would survive, and the rescue teams would find him. But that knowledge was cold comfort in the face of the losses he had suffered today.

Though it had taken six of the xenos' twisted ships with her, the Phalanx was dead. As he watched, her reactors – engines that had slumbered for centuries before Rogal's engineers had roused them – finally detonated. With her, thousands of his most valuable crew and advisers died, as well as hundreds of lesser diplomats and administrators who had helped him to keep the Cluster under control. This was a disaster far worse than the loss of the Phalanx's firepower, and it could well mean the end of the Inwit Cluster. Compared to it, the loss of the few relics he had kept in his private chambers aboard the ancient ship were not even worth mentioning – and yet, to his shame, he could not deny feeling a pang of pain at knowing they were lost as well. There was a lesson there : his men had sacrificed themselves to protect him because that was necessary. Because they believed that he had the strength to save Inwit from the threat of the Orks.

Looking at his castle burning in space, Rogal of the House of Dorn vowed that, no matter the cost, this sacrifice would not be in vain.

Dorn was forced to turn more and more of his people into soldiers, and to divert an ever-increasing part of the Inwit Cluster's resources to the war. While the Primarch fought on the front lines, discord spread amongst his people, who began to doubt his leadership in the front of the casualties taken and their diminishing standards of life. Analysis of the tactics employed prove that Dorn waged war with all the genius and skill of one of the Emperor's sons, but the human mind is not so easily convinced when one's children are taken to go fight and die against the greenskins. Dissent spread in the Inwit Cluster, and Rogal Dorn was forced to waste precious military resources putting down several outright rebellions against his perceived 'tyrannical' ways, which allowed the Orks to advance further, turning entire worlds to ruins as they did so. Thus the seed of bitterness was planted in Dorn's heart : while he did all he could to protect his people, they were turning against him, blind to the necessities of war. In response, he instated martial laws on all planets still under his forces' control, turning his policy toward civilians a lot harsher than they had previously been in an attempt to avoid further troubles.

It was at this point, when all hope seemed to be lost and Dorn's forces prepared for one final confrontation against the green tide, that the Emperor arrived. With a hundred ships accompanying His own flagship, the Bucephelus, He came to the aid of His son. The Orks, surprised by the sudden reinforcements, retreated after the Master of Mankind boarded one of their foul vessels Himself, accompanied with His Custodians, and slew the Warboss that had gathered the force attacking Inwit. The Emperor was reunited with His seventh son, though the reunion was hardly the occasion of celebrations other instances of the Emperor finding one of the lost Primarchs had been. Inwit was lost, its surface turned into a wasteland and infected by the greenskins. The planet was evacuated and bombed from orbit, while Rogal and his father watched as the former's homeworld burned at his own command. The Master of Mankind then promised to His son that he would have his vengeance against the craven aliens, for there was an army he was to command : a Legion shaped in his image, born of his blood.

Astropathic messages were sent from the Emperor's own choir, and the Great Crusade's forces heeded the will of their supreme lord. From all the galaxy, the Seventh Legion came to the ruins of Inwit, and helped crush the Ork Waaaaagh ! so completely and with such fury that, even to this day, ten thousand years later, the greenskins still avoid this region of space. Once the planets had been freed of the xenos taint – though they were deemed lost to Mankind after the battles were done – the Legion, led by its Primarch, systematically destroyed every alien empire that had sent forces to Inwit. The Emperor fought alongside Dorn on this battle, soon joined by Horus, who had been directing other campaigns. In time, another Primarch, Mortarion of the Death Guard, came to join the crusade against the Orks. These wars came to an end on the world of Gyros-Thravian, where the three sons of the Emperor fought together against the forces of the Ork Warboss Gharkul Blackfang.

In that bitter war of vengeance, Dorn was reunited with his sons and learned their strengths and skills. The Seventh Legion had many reasons to embrace its Primarch's teachings about military strength and the need to impose order to the galaxy. In its early days, it had been used by the Emperor to help into the Unification. Terra hadn't then been the greatest jewel of the Imperium of Man, but a world torn apart by millenia of warfare and divided between hundreds of factions led by madmen and genocides. By the time the first Astartes were created in the Emperor's secret laboratories, most of the conquest of the Throneworld was done, but pockets of resistance remained, and the rest of the Sol system was yet to be added to the fledgling empire. The Seventh Legion were at the vanguard of such conquest forces, fighting against the many horrors of the Old Night that still haunted Terra. For their bravery and the determination with which they had thrown down the remains of the darkness, they had received the name 'Imperial Fists', for to witness them in war was to see the incarnation of the Emperor's wrath. Now, with their Primarch to lead them, they were ready to return to the Great Crusade, and bring illumination to the stars with bolter and blade.

The Great Crusade

In the Inquisition's forbidden archives of the Great Crusade's early days, the Imperial Fists are recorded as one of the most disciplined and honorable Legions. The fury they displayed when fighting against xenos breeds was almost unparalleled amongst the Astartes – and woe betide any greenskin that crossed their path. The Seventh Legion specialized in overwhelming attacks against the enemy's headquarters, and became masters at the art of taking fortresses or reducing them to rubble. This was due to the change in Dorn's war philosophy after the loss of Inwit : rather than fortifying one's domain, it was best to crush the enemy's before he could become a threat.

The grief of losing his homeworld to the depredations of the xenos marked Rogal Dorn deeply, and this reflected on his Legion. While none of his brothers would ever dispute Dorn's ability as a general, his character rose concerns long before the Heresy. Most of the other Primarchs had a monolithic personality, whose strength could make mortal humans faint simply upon meeting them. Dorn, however, was a conflicted and tormented soul, dwelling on his failure to protect Inwit and subject to violent mood swings. Sometimes he would obsess with glory even at the cost of his men's lives, others he would go to any length to win with as little losses as possible. This duality was mirrored amongst his Legion. The two highest officers of his Legion, Sigismund the First Captain and Archamus the Master of the Huscarls – Dorn's own personal guard – incarnated this duality. While Archamus was the voice of reason, as befitted his rank as a Primarch's protector, Sigismund was Dorn's champion, his wrath unleashed upon his foes. He led the Templars of the Imperial Fists, always at the forefront of the battles his Company took part in, and earned much honor and recognition during the Great Crusade.

'What is our life ?
Duty.
What is our purpose ?
Duty.
What are we ?
Our oath.
Without our oath, what are we ?
Nothing.
What is our oath ?
Everything.
To whom do we owe our oath ?
To the Emperor and the Primarch.'
Canticle of the Templars, during the Great Crusade

Rogal's militaristic beliefs led him to impose an absurd level of discipline on his Legion, punishing failure by flogging or outright execution. While some of his brothers opposed these changes, ultimately it was up to Dorn how he wanted to lead his Legion. The Seventh Primarch was often blunt, never hesitating in speaking his mind, and many of his brothers were infuriated by his criticism of their methods of warfare. He accused Alpharius of cowardice, Magnus of dangerous over-reliance on psychic powers, Lorgar of naivety, and despite their similar martial beliefs, almost came to blows with Angron. But it was with Perturabo of the Iron Warriors that the lord of the Imperial Fists had the most hostile relationship.

The Fourth and Seventh Legions only ever fought one campaign together. On Shravaan, the Iron Warriors and the Imperial Fists waged war alongside the Emperor's Children and the Luna Wolves against the xenos breed known only as the Badoon. The details of that war are lost to time, but the aliens were crushed by the might of the four Legions with ease, as could be expected. However, at the end of the campaign, a violent argument broke between Dorn and Perturabo, and their Legions' fleets almost opened fire on each other before Perturabo, at Horus' counsel, called off his men and left the system – but not before vowing that his warriors would never fight alongside the Imperial Fists again. Today, only the Lord of Iron himself remembers the cause of the argument, as well as his Daemon Primarch brother in the Eye of Terror.

The warsmith had insulted his sire, and though he probably didn't mean what he said, honor still demanded they meet in the circle of blades. The fate of Inwit was a subject the sons of Dorn are unwilling to speak of, and to mention it, even in jest, was something that would earn flogging were the responsible a member of the Seventh Legion. As it stood, Sigismund had no choice but to challenge Berrossus to a duel – to defeat him and remind him to mind his tongue next time he stands amongst Imperial Fists. The warsmith had refused at first, but the Templar had not let it go, calling out to the Fourth Legion's own cowardly style of warfare in an attempt to bring the other Legionary to accept the duel. It had worked, of course – the sons of Perturabo, for all their stoicism, do not accept being belittled by their cousins. Berrossus knew he couldn't beat Sigismund – he was as good a fighter as any Astartes, but Sigismund was his Legion's champion. When he finally accepted the challenge, it was less because his honor demanded it than because his own temper was aflame with the Templar's insults. It should have been a quick bout, ending with Sigismund's victory at first blood and allowing both warriors to put the incident behind them. But now …

Horror held him in its grip as he looked upon the corpse of the warrior he had called brother not three nights ago. That had not been his intent. The Iron Warrior was a bit slower in a parry than the Templar had anticipated, and the sword pierced straight through his unarmored chest, puncturing his two hearts and killing him before the warsmith had the time to blink. Accidents like this had happened in the training and dueling circles before, but for Sigismund, it was the first time he has killed another of his kin, and the blood on his hands seemed too red, to rich. As he looked at them, the rest of the room explodes in furious shouts. There were many onlookers for this fight, both from his Legion and from the Fourth. And they had all seen him kill Berrossus.

This, he thought, was going to have consequences. He just didn't know just what these consequences would be.

Decades later, when Perturabo called Horus and his father for help in destroying the Ork empire of Ullanor, he deliberately ignored Dorn, despite his brother's undeniable skill at fighting the greenskins. This made the rift between the two Primarchs even deeper, and the Imperial Fists began to spread rumors about the Iron Warriors, calling them cowards who hid in their fortresses and attacked their enemies from afar with their artillery rather than fight at the front of the Great Crusade like honorable warriors.

When the Emperor called for the Council of Nikaea, Dorn didn't take any position in the debate. His Legion had always used a Librarium, but even if he acknowledged its utility, the Primarch of the Imperial Fists still distrusted the users of psychic powers. As the Emperor's judgment was pending, he gathered all his Librarians aboard his flagship, so that following his father's decision, whatever it may be, would be easier. However, before the Master of Mankind gave His decision, a terrible accident killed all those who had been gathered, crippling the Imperial Fists' Librarium. Rogal, who had been waiting with several of his brothers, returned to his ship in haste, only to find the corpses of his sons and entire sections of the vessel melted, as if some cataclysmic fire had occurred.

Massac and his brothers were fighting with all their strength, and it wasn't enough. Their swords blazed with psychic power, each strike cutting down one of their hateful foe – but for each one they fell, another two took its place. There was no hope of reinforcement from the rest of the ship : the first thing the thousand Librarians had done when the Warp had broken through had been ordering the whole section sealed, and non-psykers combatants would be a liability against such creatures as they faced anyway.

The reek of blood and iron was overpowering, passing straight through their hoods' filters as though they weren't there. The beasts before them were not of any form that could be described in words : they were and weren't there at the same time, leaving impressions behind them, shadows of memory that left burning marks the shape of old Earth's mythical diablos on the psyche of the warriors. These were things of the Empyrean pouring through reality by crossing … what, exactly ? It wasn't uncommon for the predators of the Warp to attack Imperial vessels when their Geller Field failed during transition, but the ship was out of the Sea of Souls, immobile near the edge of the Nikaea system. Yet warp-fire had burst out in the very heart of their gathering hall, where they had sat in meditation, waiting for the Emperor's decree, and from it had come the beasts. Now there was a great rent in reality, through which images of pure madness could be seen.

With a combined burst of psychic power, they burned the current wave of creatures to red ash that quickly dissolved as the laws of reality reasserted themselves. But already the breach was acting again, and another of the warp-born emerged from it. This one, however, wasn't one of the mindless predators of rage and bloodshed the Librarians had fought previously. It was a towering monstrosity of red muscles and black iron, holding in each of its hand an axe bearing runes that burned with unholy fire. And while the other beasts had screamed their hatred in wordless shouts of impossible sounds, when this one spoke, Massac's tortured mind understood its meaning :

'I am Skarbrand, witches. I am your end !'

Behind this being – this lord of the damned, this prince of bloodshed and hatred – came thousands more of the lesser creatures that had already whittled down the Legionaries' numbers. And it was then that the six hundred and fifty-six remaining sons of Dorn trapped with the daemons started to die, while Khorne laughed in the Sea of Souls.

The last Librarians of the Imperial Fists were those who hadn't been present at the gathering, having been delayed for one reason or another. In later years, they died one by one in apparently ordinary deaths, while implantation of Rogal's gene-seed unto young psykers failed systematically. When the Heresy began in earnest, none of them were still alive – which was probably a blessing in disguise, as their fate amongst Khornates would have been an unpleasant one. For centuries, the Inquisition and the Thousand Sons have investigated this matter, and have found nothing. This total absence of evidence has led some to believe the Dark Angels were involved, having engineered the loss of the Seventh's psychically gifted sons in order to leave their Primarch exposed to the touch of the Blood God. Though this remains only a theory, it is true that Dorn's character changed for the worse after Nikaea.

Beyond his sorrow at the loss of so many of his sons to what appeared at the time to be random chance, Dorn was furious at being passed over in Perturabo's favor. In his eyes, the glory of being the Emperor's Praetorian belonged to him and his Legion, not to his rival's mud-diggers. While Perturabo left Nikaea with one of the greatest honors to be ever bestowed upon a Primarch, Dorn's Legion was crippled, bereft of the support of psychic powers the Emperor Himself had decreed were a necessary part of the Great Crusade. In the years that followed, the Imperial Fists redoubled their zeal in the Great Crusade, claiming more and more worlds for the Imperium despite the fact that their Librarium never recovered from its losses. At the same time, the recklessness of Dorn and his commanders increased, as did the losses they took for every victory. To compensate, entire generations were stolen away from the planets the Seventh conquered, leaving collapsing civilizations in the wake of their Expeditionary Fleets. Reports were sent to Horus and Terra, but such was the scope of the Great Crusade that it would take a lot more than civilian complaints to cause censure against a Primarch. Then came the Cheraut Incident.

The Cheraut system was home to a confederation of human worlds who refused their integration into the Imperium. For years its rulers had resisted the Imperial war machine, and things had reached the point where Warmaster Horus asked three of his brothers to solve the problem once and for all – a deployment of force rarely seen in the history of the Great Crusade. Fulgrim of the Emperor's Children, Dorn of the Imperial Fists and Curze of the Night Lords brought the elite of their Legions to Cheraut. Where the Imperial Army had toiled in vain for so long, the Astartes broke the back of the resistance in mere months.

The leadership of the defenders was eliminated by strike teams of the Night Lords, while the Seventh and Third Legions destroyed their strongholds one by one. Ninety-four days after the Primarchs' arrival, the Cheraut system surrendered to the Imperium. However, in the ruined streets of what had been the confederation's capital, Konrad Curze saw his brother Dorn ordering the execution of the prisoners, despite their commanders' capitulation.

Curze was driven furious by the sight. He confronted his brother, demanding that his men cease their exactions this instant, and left the area to his own Legionaries' care. But Dorn denied the Savior of Nostramo. He told Konrad that these men had to be punished for daring to resist the Imperium, lest others do the same and bring the whole empire down, exposing Mankind to the xenos. He accused the King of the Night of cowardice, claiming that Curze was too weak to do what was necessary, and that his protecting of mortals would only make the species weaker and, in time, doom it. At this, the Primarch of the Eighth Legion lost his calm. He attacked Dorn, and nearly killed him before Fulgrim pulled him off the lord of the Imperial Fists. Later, the Phoenician would learn that Curze had acted not simply out of fury at having his beliefs and ideals dragged in the mud, but because Dorn's words had triggered a vision of apocalyptic destruction and betrayal. By the time the truth of that vision would be revealed, however, it would be too late.

Dorn left Cheraut with his Legion at once, leaving his two brothers to deal with the system's compliance. He was furious at Curze's insults and assault, vowing that he would make his brother pay for the affront. At the same time, the words of the Savior of Nostramo echoed in his mind, and he began to doubt. He knew Curze was one of his father's favorite sons, and that his views were likely those of Him of Earth as well. Besides, despite his scorn for Perturabo, he knew that the Lord of Iron harbored similar thoughts. Both of them refused to acknowledge the inherent weakness of Man, and the necessity of the strong leading them, with or without their accord. In Dorn's eyes, this attitude would only lead to more destruction like what had befallen Inwit. It was as he brooded over this that the Seventh Primarch received a message from his brother Roboute Guilliman.

The Arch-Traitor told his brother the same lies with which he had infected his own Legion : that the Emperor was weak, and had abandoned the Great Crusade, leaving the galaxy His sons had conquered for Him into the hands of unworthy mortals. Even Horus, once the greatest of them, had reduced himself to a mere diplomat, even now trying to negotiate peace with a degenerate human culture which consorted with xenos. That particular information ignited Dorn's rage, for the Warmaster had been one of the few he had trusted and admired amongst his brothers. Yet the proof Guilliman showed him – picts and official communications from the so-called Interex – were impossible to deny. Guilliman told Dorn of his desire to return the reins of the Imperium to those who both deserved them and were capable of making the choices necessary for Mankind to survive. And to do that, he needed the help of Dorn, who knew more than any other the need for strong leadership and the risks of allowing mortal humans to guide the destiny of the species.

Rogal Dorn fell for his corrupt brother's lies, and pledged himself and his Legion to the cause of Guilliman's rebellion. In return, the lord of the Ultramarines told his brother of his plans, and of the place where they would be put in motion : a five-planets system known as Isstvan.

The Heresy : Atrocity and Massacre

Isstvan had been brought to compliance several decades ago, by a contingent of the Raven Guard. According to the records of the Great Crusade, it had been a model compliance, if not a peaceful one. The people of Isstvan had resisted the coming of the Imperium not because they didn't want to be reunited with Terra, but because the Imperial Truth had conflicted with their religion. It had taken several months to the Nineteenth Legion to crush their temples and demonstrate in the clearest way that their gods weren't real and that they didn't need fear their retribution, and the compliance had been easy after that.

When the Imperial Fists arrived, however, the system was in open rebellion. Vardus Praal, the Imperial Governor put in place by the Raven Guard had abandoned his oaths and joined the old cults of Isstvan, who had apparently survived the purges of the Astartes. The entire planet had followed him in his rebellion, or been purged in turn. Had Dorn not known the true hand behind this rebellion, he would no doubt have condemned Corax for his failure to pacify the planet correctly.

Four Legions had gathered at Isstvan, a number never seen since the Triumph of Ullanor. The Ultramarines, the Blood Angels, the Iron Hands and the Imperial Fists were there, and many who didn't know what was to come wondered what in the system could possibly warrant the use of such overwhelming force. The official reason was that Guilliman had asked his brothers to come in order to demonstrate that the Imperium would not tolerate dissensions within its own borders, but that excuse was flimsy at best. Still, none could possibly have anticipated the true horror of the situation.

The four Primarchs held council together, and a plan was designed to retake the planet and punish the ringleaders of the rebellion. All Legions would send select elements to the third planet of the system, the only one populated. These groups of warriors would seek out specific objectives and secure them before a second wave of warriors was sent. The planet would fall before the end of the day – as was only fitting for a world faced with the combined might of four Legions.

But all Inquisitors know what happened instead. The Primarchs had sent to Isstvan those of their sons they didn't believe would follow them into betrayal and infamy, choosing to purge their Legions of loyalty to the Emperor before beginning their own dark crusade against the Master of Mankind. While their sons fought against the rebels, they ordered their fleets to open fire on the planet. They unleashed the Life-Eater virus, a weapon which use was forbidden to all but the Emperor's own sons. The first shells of the bio-engineered plague hit the ground at the same moment the Astartes claimed victory against the rebels. In mere moments, the terrifying bio-weapon swept the planet clean of life, killing eight billions of civilians and inflicting horrible casualties to the deployed Marines, before the fleet opened fire again, igniting the gas released in the atmosphere by the Life-Eater and cleansing it in an ocean of fire.

Yet the plan of the Arch-Traitor didn't go unopposed. Despite the investigations of the four traitor Primarchs, there were those in their Legions who had remained loyal and avoided being sent on Isstvan. When the orders came to bombard the planet, these few loyal souls warned their brothers of what was to come, before attempting to leave the system and bring word of the Atrocity to Terra. Of the few ships who were taken by these loyalists, only one managed to leave before being either boarded or destroyed : the Tribune, a battle-barge of the Seventh Legion, commanded by Captain Alexis Pollux. It was that vessel that would bring word to Terra of what had occurred.

Thanks to the warnings they received, some of the Astartes on the surface managed to hide in bunkers and tunnels deep enough for them to survive the viral bombardment. They emerged from their shelters to witness utter desolation : billions of fire-bleached corpses, and the ruins of entire cities. Worse, they knew who was responsible. The rebels of Isstvan couldn't possibly have access to such weapons, nor could they have had the resolve to use them on their own people.

'We are betrayed.'
Anonymous Legionary, on the fields of Isstvan III, moments before the viral bombardment.

Words fail to convey what the loyalists must have felt at that terrible realization. Astartes are made for service, for duty, for loyalty to their battle-brothers and commanders. The bonds of brotherhood are one of the few things they are allowed to keep from their time as human beings, and for these bonds to be shattered in the act of Heresy is something which can break the spirit of the even the most stalwart servant of the Emperor. And yet, betrayed by their fathers and abandoned by their brothers, the Martyrs of Isstvan III fought on. They swore oaths of revenge on the traitors, and prepared for what they knew was to come. For the first time in recorded history, the hour was at hand where Astartes would kill Astartes on the battlefield.

In orbit, the traitor Primarchs witnessed their failure to purge their Legions in a single shot. Almost immediately, Dorn descended on the planet to finish them, accompanied by the bulk of his Legion and quickly followed by the Ninth, Tenth and Thirteenth Legions. The Primarch of the Imperial Fists told Guilliman, who wanted to kill the surviving loyalists from orbit, that they had already survived the worst their fleet had to offer. Only by killing them in person could they be sure they had disposed of their disloyal sons. Thus began the first battle of the Heresy. Despite the crushing numerical superiority of the traitors, they fought to the last and for weeks, holding the forces of the rebellion in place and giving time for the warning to reach Terra. Thousands of Legionaries had survived the initial bombardment, and they died as they had lived : as true servants of the Emperor. Today, there is a monument dedicated to them on Terra, that bears no name, for it is unknown who of the traitors' sons stood loyal and who fell. Instead, the Pillar of Bone is covered in prayers for their souls and oaths to never forget nor forgive.

The Tribune emerged from the Warp. Its once proud shape was marred with the scars of the damage it had sustained while escaping Isstvan, as well as the depredations of the Empyrean's beasts – Alexis was unwilling to call them, as most of his crew and surviving brothers did, daemons. Of the hundred warriors who had been under his command before, barely thirty remained. Twenty he had had to kill, for they had refused to follow him, instead choosing to stand with their Primarch in his madness.

Before him, through the occulus, he could see the heart of the Imperium floating in space. Thousands and thousands of ships were swirling around, carrying merchandise and men for the insatiable Throneworld. Among them were the ships of the Iron Warriors, those worthies who had been chosen for the duty of protecting Terra and the Emperor. Once, Alexis had been jealous of them. Now, he could only admit, however bitter that made him, that the decision of the Master of Mankind had been the right one. Who knew what would have happened, had Dorn been in command of the Imperial Palace's defenses during his betrayal ?

But there was something wrong, and it took one more minute for the captain to see it.

'Where is the Ironblood ?' he murmured to himself, though his brothers picked it up easily. 'Where is Perturabo ?'

'Lord Pollux', said one of the few remaining bridge crew. 'We are being hailed.'

Alexis nodded, and the vox officer opened the channel.

'Imperial Fist vessel,' said a voice with the distinctive sound of an Astartes, the tone of a commander, and the caution of a man who doesn't trust the one he was speaking to. 'This is Warsmith Forrix of the Fourth Legion. Identify yourself and state the reason of your presence in the Solar system.'

'My name is Alexis Pollux. Once a captain of the Legione Astartes. Once a son of Rogal Dorn. And I have come here to warn you of betrayal, son of the Praetorian.'

Eventually, word reached Terra of what had happened, just as Warmaster Horus returned from the Interex with new knowledge of the perils of Chaos. In haste, a force of seven Legions was ordered to converge on Isstvan and annihilate the traitors, while two more Legions, the Word Bearers and the Eaters of Worlds, were dispatched to Ultramar. While the hammer of the Emperor approached, the Traitor Legions fortified the fifth planet of the system, creating a stronghold that could hold against the retribution of the Imperium. Of course, even then, the four traitor Primarchs knew that amongst their seven brothers Horus had sent, four had already pledged themselves and their warriors to Guilliman's cause.

During the Dropsite Massacre, Dorn fought with his mighty chainsword at the head of his Legion, butchering hundreds of loyalists with unbridled fury. Contrary to Guilliman's plan, he refused to give ground, and the traitors took greater casualties than they had anticipated before the Dark Angels, White Scars, Salamanders and Raven Guards arrived to join the fight and reveal their true allegiances. Dorn sought out Konrad Curze, wanting to avenge his humiliation on Cheraut, but he was no match for the cold fury of the Savior of Nostramo. The Primarch of the Night Lords almost succeeded in killing his brother, but was stopped by Sanguinius and forced to retreat before going after Vulkan and meeting his fate at the Black Dragon's hands.

When the Massacre came to an end, hundreds of thousands of Legionaries had died. The Alpha Legion and the Death Guard had taken horrendous losses, and the Night Lords had lost their Primarch. Word arrived from Guilliman's agents in Ultramar that the Ruinstorm had been unleashed, trapping the Twelfth and Seventeenth Legions in his fief. The Heresy could now begin in earnest, and spread across the entire galaxy as it made the Imperium burn.

The Blood Crusade

While the Ultramarines advanced on Terra, the Imperial Fists spread across the Imperium, burning all the Iron Warriors fortresses they could find on the way. Released from the constraints of Imperial law, the Seventh Legion fought with a ferocity that belied the cold facade they had shown during the Great Crusade. Determined to show their strength to the rest of the galaxy, they sought to test themselves in battle against the most difficult of enemies : the Iron Warriors and their fortress-worlds.

As the Heresy raged on, however, Rogal Dorn noticed that there were changes ongoing in his Legion. Soldiers who had been the most disciplined of the Astartes were growing wild, seeking bloodshed above victory and glory in battle over tactical objectives. What he had seen of the Ultramarines' corruption was now beginning to appear inside his own Legion, but without the control and focus of the Thirteenth. Instead, his sons were degenerating, consumed by their wrath at the Imperium who had betrayed them. Losses were increasing with every battle as the command structure and discipline of the Legion broke down, especially considering that the Seventh was waging war against the Iron Warriors' fortress worlds.

The situation came to a head during the battle for the Shadenhold, on Lesser Damantyne. There, the Imperial Fists faced the defenses of Warsmith Barabas Dantioch, one of the best fortress-masters of the Fourth Legion. Thousands of Legionaries, millions of mortal soldiers, and several Titans from the Legio that had chosen to stand with the arch-betrayer Guilliman laid siege to one of the most ingeniously devised fortresses in the history of the galaxy. For three years Dorn laid siege to the Shadenhold, and as time passed entire Companies of his Legion hurled themselves into Dantioch's defenses, heedless of their Primarch's orders, consumed by the desire to reach their foe at last. Infighting broke out between his Legionaries and mortal allies, as the lust for blood grew amongst the sons of Dorn as they were denied the chance to face the loyalists in direct conflict.

Finally, Dorn managed to breach the warsmith's defenses, only to find that Dantioch was gone. The son of Perturabo had escaped and rigged the Shadenhold – built inside a gigantic stalactite in a subterranean cavern – to detonate. The Primarch of the Imperial Fists barely escaped with his life, but the total toll taken by the siege on his Legion was appalling. It is estimated that more than a tenth of the Seventh's total strength was lost thanks to Barabas Dantioch – a deed that has led to the warsmith's beatification by the Ecclesiarchy. Seeing the terrible damage done to his armies, Dorn realized that his Legion was killing itself.

His whole body throbbed in pain, and he was alone. Something had gone wrong when he had activated the teleport, though he would likely never know exactly what.

'What are you doing here, Iron Warrior ?' asked a voice that was unlike any voice he had ever heard. It was a voice that was filled with gravity and nobility alike – the kind of voice that could make armies lay down their arms in shame, and turn fanatics away from their false idols.

He looked up, and saw a figure in grey armor that somehow appeared to be shrouded in golden light, even though no sun shone in the hellish skies. He knew these features, though he had never seen them in person. They were depicted on thousands of remembrancers' works and on propaganda posters for the Imperial Truth all across the galaxy.

'I do not know, lord Lorgar,' said Barabas Dantioch, kneeling before the Primarch of the Word Bearers.

Rogal Dorn sought the counsel of his brother Guilliman, whose knowledge of the Warp was unrivaled amongst the traitor Primarchs – safe perhaps for that of Lion El'Jonson. Roboute told his cohort that the Blood God, Khorne, had marked Dorn's Legion with His sigil, and that it was the Chaos God's influence that was transforming the Seventh more and more quickly. While he honored the more martial aspect of the God of War, Dorn also didn't want his Legion to become mindless berzerkers, or die out before the Heresy could even reach Terra and face the greatest challenge of all : the Imperial Palace.

That is why, with the help of the Ultramarines, he made a pact with Khorne. In return for their eternal service, the Imperial Fists would be protected from the madness that was threatening to consume so many of their numbers. This protection came at a price in blood that the Legion payed without hesitation. For three years, while the Heresy advanced toward Terra, the Seventh Legion gathered its strength and burned a hundred civilian worlds, killing hundreds of billions of innocents in an offering to Khorne in order to seal the pact. This carnage was later recorded in Imperial archives as the Blood Crusade, and in time, that name would be attributed to other large-scale actions of the Seventh Legion.

The fury burned in his veins like a holy fire. It was filling his muscles with strength, accelerating his reflexes and lifting the fatigue from his limbs. Not that he would have needed this blessing to slay his current targets. The population of the Phall system was utterly defenseless in the face of the Blood Crusade, and there had been a time when the slaughter of such weak prey would have annoyed him. But he knew now that this was an offering, a proof of faith and dedication to the Power that had marked them all as His. The weak had to die so that the strong could remain strong. Such was the way of the universe – the Fists were merely speeding up the process.

Sigismund's blade tore another of the fleeing civilians in two, and the Templar looked up at the sky, which were already starting to shine with the sacred red of the God of War as the Seventh drew His attention by the offering of billions of lives. No matter how many times he saw it, it always filled his heart with savage joy and pride – for he knew that the eyes of the Blood God were upon him more than any of his brothers.

'Blood for the Blood God !' he shouted, letting some of the fire in his heart spill over to his brethren. 'Skulls for the Skull Throne !'

By the end of the Blood Crusade, the Seventh Legion had gone from Traitor to Chaos Marines, as the Dark Angels did when their Primarch returned from the Maelstrom. No longer did they fight alongside Guilliman in order to bring order to the Imperium and protect it from the horrors of the stars : they fought for glory and the favor of Khorne. To mark their allegiance to the Blood God, all Imperial Fists painted their gauntlets in red. This tradition, kept ever since, has led the loyal Legions to call the Seventh the Crimson Fists rather than their original name, denying their traitorous kin the qualifier of Imperial.

His Legion saved from madness at the cost of their immortal souls, Dorn turned his gaze to the ultimate objective of the Heresy : Terra, and his brother Perturabo's fortifications. There, he knew, would the final battle for the fate of the galaxy be waged. There, he would prove that he was the strongest of them, and always had been.

The Siege of Terra

'The skies burned with fire. The Fallen Angels descended upon Holy Terra on wings of treachery and falsehood, and hurled themselves at the great walls of the Imperial Palace. And leading them, before even the blue-clad arch-traitors, stood the scions of blood and carnage, their honor forsaken and their hands forever red with innocent blood …'
Excerpt from The Canticle of the Dead

The Imperial Fists were at the forefront of the renegades' assault on the Imperial Palace. With the new blessing of the Blood God, they were capable of cooperating with the other Traitor Legions. But even with the fury they felt at Perturabo's sons under control, the Lord of Iron had turned the Imperial Palace into such a bastion that they took terrible losses for each meter of ground they managed to take. The absence of the Blood Angels, who had been supposed to support the advance of the Seventh but instead preferred to sate their blasphemous thirst on Terra's population, made the situation even worse.

The Siege lasted for weeks, and as it went on without any significant gain made for the traitors, dissension began to spread amongst their ranks. The opposing powers that had claimed the souls of the Traitor Legions started to be reflected in their mortal slaves, and it is believed that in time, they would have turned on each other – for Guilliman lacked the ability to inspire his brothers to truly stand by him, and had instead drawn them to rebellion by appealing to their own desires and grievances toward the Imperium.

The death of Horus at Sanguinius' hands was the only thing that prevented the other Traitor Legions from directly turning on the Blood Angels for refusing to fight alongside them on the walls, and when the Ninth Legion finally joined the fight, it seemed that the rebels were about to break through and invade the Palace. Then the Night Lords and the Emperor's Children arrived, and it is said that Dorn's scream of rage at the coming of Curze's sons shook the walls of the Inner Sanctum itself. The Ravenlord left the surface of Terra to face the two Legions in orbit, while Vulkan remained to face the forces of the Eighth Legion, which seethed with the desire to avenge their Primarch.

Meanwhile, Guilliman received words from his allies in the Warp that Lorgar and Angron had managed to escape the Ruinstorm, using an ancient xenos artifact, the use of which had been unlocked for them by the most unlikely ally. Time was running out for the traitors, and if the Imperial Palace still stood defiant by the time the Word Bearers and World Eaters arrived, then all would be lost. The Arch-Traitor called his three remaining brothers to him : Ferrus Manus, Rogal Dorn and Lion El'Jonson, and launched his final gambit. Together with their Legions' elite, they broke the Eternity Gate of the Palace, and three of them advanced into the Sanctuary while Manus held the gates against any loyalist counter-attack.

They found in their way a thousand Iron Warriors, led by Warsmith Kroeger, one of the Triarchs of the Fourth Legion. Seeing the forces of his most hated brother, Dorn demanded that he led the charge, and slew the warsmith in single combat after more than an hour of bloody close-quarters fighting. But while he may have killed the son, the father wouldn't go down so easily.

In the Cavea Ferrum, Dorn faced Perturabo. After hours of fighting, he broke his sword in a blow that threw down the Lord of Iron and his warhammer away from him, and was preparing to finish him with his bare hands when word came through the vox of what had happened in the Throneroom. Guilliman was dead. Angron and Lorgar were almost here. The rebellion had failed. Screaming with unspeakable rage, Dorn was forced to retreat, leaving his rival alive, and run from Terra with his Legion, to the Eye of Terror, where the Imperium's vengeance wouldn't be able to follow him.

Post-Heresy : the Iron Cage and the Breaking

Sigismund the Destroyer
During the Great Crusade, Sigismund was the First Captain of the Seventh Legion and generally hailed as the greatest son of Dorn. It was Sigismund and his Templars that carried Dorn's banner on the field, and it was him who fought as the Primarch's Champion. The First Captain was a consummate killer and an exceptional duelist, fighting against the best warriors of other Legions in the training cages and never losing one of these bouts. Abaddon of the Luna Wolves, Lucius of the Emperor's Children, Kharn of the World Eaters or Amet of the Blood Angels : none could defeat him. The only one to ever avoid defeat at his blades was Sevatar, First Captain of the Night Lords, who head-butted him unconscious after hours of dueling, making the bout a tie. At that time, Sigismund was acknowledged as an honorable warrior, and greatly appreciated in many Legions, despite being somewhat prideful and humorless.
On Isstvan III, Sigismund was part of the forces who took part in the massacre of their brethren. Many champions of the loyalist elements fell to his blade, a feat that he would later repeat on Terra. It is believed that these kills were what drew the attention of the Blood God to him, and that his part in the Breaking was what earned him the title of Chosen of Khorne, a position he still holds to this day despite the attempts of many other followers of the Lord of Skulls to take it from his headless corpse.
It is said that the sword that Sigismund now uses was forged from fragments of Dorn's own weapon, which he shattered in his duel against Perturabo – the blade breaking with the strength of the blow that threw down the Lord of Iron. He reforged it on the new homeworld of the Legion in the Eye, with the help of Khorne's own daemon blacksmith.

Less than a century after the end of the Heresy, Dorn, who still ruled his Legion as a Primarch in the Eye of Terror, sought to escape his hellish prison. He knew that Perturabo had created a circle of defenses around the Warp Storm, and was filled with the need to crush it, in order to prove that he was superior to the Lord of Iron. He learned which of the fortress-worlds was commanded by Perturabo himself, and gathered as many ships, Legionaries and daemonic allies as he could, before launching the first massive attempt from the Traitor Legions to break free of the Iron Cages. The Iron Warriors were forewarned of the incoming attack by their own Librarians and astropaths, who felt the pulses of hatred flowing ahead of the Chaos fleet, and the world of Sebastus IV prepared itself for war against the traitors.

The world was too well-defended to be razed from orbit, but Perturabo taunted his brother by lowering the void shields for a fraction of a second each hour – not enough time to fire through the opening, but enough to teleport troops on the surface. Enraged by the provocation, Dorn used Warp-born technosorcery to teleport himself and half of his remaining Legion to the world – and straight into the Lord of Iron's trap. The surface of Sebastus IV was a labyrinth filled with death traps and automated defenses. Hundreds of thousands of skitarii warriors had been given to Perturabo for this occasion, and with the aid of the Iron Warriors commanding them, they tore the Imperial Fists to pieces. Dorn himself may be all but impossible to kill, but he couldn't be everywhere at once. After hours of punishing warfare, Dorn finally reached the center of the labyrinth, where he believed Perturabo waited for him. But the Lord of Iron was no fool, and honor and glory meant nothing to him – something Dorn had always failed to understand. Instead of finding his brother, Dorn found tons and tons of explosive, rigged to detonate the moment he entered the room. His Huscarls, warriors who had fought at his side since the dawn of the Great Crusade and had followed him through the entire Heresy, died to a man trying to protect their Primarch from the explosion – including their leader, Archamus, who had always been the voice of reason in Dorn's councils. The Primarch of the Seventh Legion barely survived, and was gravely wounded.

His body broken, his Legion decimated and his fleet aflame, Dorn was forced to retreat back into the Eye of Terror. It was the final time he and his brother ever measured their skills in warfare against each other. The Imperial Fists had lost thousands and thousands of warriors in that ill-fated assault, but the blow that would truly destroy them as a Legion was yet to come – and when it did, it did from the most unexpected source : Sigismund himself, the most loyal son of Dorn, captain of the First Company and leader of the Templars.

'You are not my father. And I am not your son.'
Last words of Sigismund to Primarch Rogal Dorn

The Legion retreated to the daemon world of Esk'Al'Urien, where the Imperial Fists had established their principal stronghold. But as they began to heal and repair the damage their fleet had taken, the First Captain of the Legion and his men began to slaughter their own brothers and their mortal servants and allies. With no warning nor reason given, Sigismund turned on his own bloodline and sought out the remaining leaders of the Seventh – captains and fleetmasters whose reputation and skill could have united the Legion while the Primarch recovered from the wounds he had taken. Chaos spread across the entire daemon world, and hosts of Neverborn incarnated from the bloodshed, reaping an even greater toll on the Imperial Fists' numbers. In the absolute confusion, companies began to fight each other even without Sigismund's presence. It seemed as if the Seventh Legion was going to destroy itself … and then Dorn rose.

The ground was slick with his sons' blood. The skies were burning with the fires of Hell. His whole body was aflame with the pain of his injuries. Grafted skin was falling from his exposed muscles as he advanced toward the sounds of battle, but he ignored it. It was only pain. What mattered was what his world was under attack. Who dared to attack him here, where his Legion was at his strongest ? Who thought that the Imperial Fists had been weakened enough by Perturabo's cowardly trap ?

When he emerged from his chamber and saw the battlefield, he didn't understand. There was no enemy. No Astartes wearing the colors from another Legion, no host of daemons led by a champion of one of the Blood God's enemies. Yet the air was filled with the sound of death cries and chainblades on ceramite. Cold realization set in : his sons were killing each other.

'Who ?!' he howled, anger quickly replacing doubt. 'Who dares ?!'

'I do,' said a voice he knew all too well.

Sigismund stood before him, his armor painted black safe from his red gauntlets. He wore his helmet and held in his hands Storm's Teeth, reforged after it broke against Perturabo's Forgebreaker. Dorn had never learned just how the Lord of Iron had acquired Ferrus' warhammer, and he didn't care.

'You ?' he sneered. 'You did … this ?'

'Yes. You have failed us, father. You will destroy the Legion; grind it to dust against Perturabo's Iron Cage. I will not let you do it – even if it means I have to destroy the Legion myself.'

'You … you …'

Hatred boiled in his veins. A red veil descended on his thoughts as he took in the true scope of the betrayal. Cracks formed in his flesh as the raw power created by such carnage gathered in him, seeking a host capable of giving it form in the semi-material realm that was Eyespace. Before Sigismund's wide eyes, the blood that had been spilled all across the planet began to flow toward the Primarch's towering figure, forming a great column of crimson fluid that reached all the way up to the tortured skies. Then the column burst apart, revealing a creature of nightmares and utter bloodlust, which looked down at Sigismund with burning hatred in its eyes.

'I will kill you,' said the Daemon Primarch in a voice that was the damnation of heroes and the death of innocents, 'my traitorous son.'

The Primarch of the Imperial Fists ascended to the ranks of the Daemon Princes on the same day his favorite son destroyed his Legion. The rage he felt that day now burns in him forever, but the one he seeks to destroy eluded him. Sigismund and his cohorts, renaming themselves the Black Templars, left the daemon world on their own ships, and Dorn has been hunting them through his daemon allies ever since. With their Primarch removed from them and thrown into the Great Game of the Chaos Gods and most of their superior officers dead at the Black Templars' hands, the Imperial Fists fractured in hundreds of small warbands, generally no larger than a single Company commanding a single ship. Only rarely in the following millenia would Dorn's attention tear from his conflicts in the Warp and his quest for Sigismund's blood to return to the world around him.

The Black Templars
When Sigismund the Destroyer left his Legion, a sizable host followed him. They were the warriors who saw the former Legion's Champion as the chosen of the Blood God, and who owed him their loyalty either because of his former rank or because of a blood debt. They became the Black Templars, in a mockery of the order Sigismund had once led as the Legion's elite. They repainted their armor in black, though they left their red gauntlets untouched. For centuries since then, they have loyally followed Sigismund throughout the Eye of Terror and beyond, seeking worthy enemies, be they xenos, servants of the Imperium or fellow traitors. On more than one occasion as the Imperium been saved from having to deal with a warlord or an alien arch-fiend when the Black Templars emerged from the Warp in order for their master to claim one more skull for the Blood God – though it has lost twice that number of Heroes to the same blade.

The Legion Wars

Several decades after the disaster of the Iron Cage and the subsequent Breaking of what had once been the Seventh Legion, the circle of defenses around the Eye of Terror came once more under attack. This time it was the Ninth Legion that led the assault, with the malformed horrors created by the arch-renegade Fabius Bile of the Emperor's Children. These were the Clone Wars, and while they would cause much horror upon the Imperium, they had also consequences in the Eye of Terror. When Dorn heard that Sanguinius' Legion had succeeded where himself had failed and broken free of the Iron Cage, his rage was immense. When he learned how the Angel had achieved that feat – by treachery and the corruption of an Imperial commander – he couldn't forgive what he perceived as a deliberate insult against his honor. Still, under the counsel of what few of his men still dared to talk to him, he held back his fury until one last insult was hurled at him by the Blood Angels.

Then the Ninth Legion attacked one of the Imperial Fists' genetic facilities, where the few non-mutated human youths the Seventh could find in the Eye were transformed in new Legionaries. The motives behind that attack are unclear : some Inquisitors believe it was an isolated act by sensations-craving Blood Angels, others than Fabius Bile ordered it in order to obtain Imperial Fist's gene-seed for his blasphemous experiments. Whatever the reason, Dorn's reaction to the laboratory's destruction and the plunder of its gene-seed's stores was as predictable as it was devastating. The War of Woe had begun.

There had always been strife amongst the Traitor Legions in the Eye, caused by old grudges, rivalries, religious beliefs, competition for limited supplies or simple need for war. Until now, however, these conflicts had been kept at the level of individual warbands, with the Legions themselves maintaining a tenuous ceasefire with each other. The Daemon Primarchs didn't want to waste their troops against their own kin, preferring to seek a way to claim vengeance on the Imperium. But the champion of Khorne changed that. Despite the Breaking of the Seventh Legion, his word still held some value amongst his sons, and the prospect of waging war against another Legion was one sure to draw the attention of the Khornate Fists. At his command, tens of thousands of Imperial Fists and millions of humans and mutants gathered in a mighty armada, with which the Daemon Primarch waged a terrible war against Sanguinius. Daemon world after daemon world burned, with hosts of daemons of the Blood God and the Dark Prince flocking to the side of both fallen Primarchs. Other Legions were drawn to the conflict, whether their own Primarchs wanted it or not.

Faced with his brother's onslaught, Sanguinius called back most of the forces he had sent in support of Fabius Bile's incursion into Imperial space. This is estimated to have significantly contributed to the ultimate victory of the Sons of Horus and Emperor's Children, for though the losses they took in destroying the renegade Chief Apothecary's so-called Black Legion. Imperial scholars who know of the Legion Wars consider them to be a perfect example of the maxim known to all Imperial commanders facing the Archenemy on the field : sometimes, the very nature of Chaos is the Imperium's best ally against its minions.

Ultimately, the two Daemon Primarchs of Khorne and Slaanesh faced each other on the daemon world of Iydris, an ancient Crone World of the Eldars located near the center of the Eye of Terror. The exact details or victor of that epic confrontation remain unknown even to the mightiest seers of the Thousand Sons, but it caused the war between the Seventh and Ninth Legions to abate, if not wholly cease – in some parts of the Eye, the sons of Sanguinius and Dorn still fight.

The weapons of the two demigods lay broken at their feet, shattered by the might of their blows. Their pieces were lost amongst thousands of dead Legionaries in yellow and crimson armor. The two had been fighting for an eternity, yet still they battled each other under the gaze of the dead of Iydris. Sanguinius' magnificent wings were broken and bloody, his glamour stripped away and the ugliness beneath revealed. Dorn's armor was covered in crack, and blood gushed from a hundred wounds – each of them would have killed a Space Marine outright.

There were no words exchanged between the two Daemon Primarchs. The Lord of Angels had tried to taunt his foe at the beginning of the duel, and Dorn had answered by scoring first blood. After that, there had been no more insults. Only the fight between the avatars of two opposed gods, while their sons watched in awe from far, far away.

Even battered and wounded, the fallen sons of the Emperor were figures of terror and wonder. They fought with their bare hands, but such was their power now that each blow could have rend a tank apart. Around them, thousands of Neverborn were born and destroyed every second as conflicting energies clashed, their brief existences spent in singular screams of hatred and despair. In the sky, the baleful un-light of the Eye of Terror's central black hole shone upon the demigods, forming a hateful trinity with the gazes of the God of War and She-Who-Thirsts.

For decades, the Blood Crusade had raged on, igniting the Eye with what was already coming to be called the Legion Wars. Though the apparent motives behind it had been understandable by the minds of mortal men, in reality, conflict between the Seventh and the Ninth had always been inevitable. With the Heresy failed, the Great Game had returned to its state of opposition between the Four, and the slaves to darkness had hailed the call to war against their patron's enemies when it sounded in their very souls. And so the Gods' champions had come to the Crone World of Iydris, to fight the final battle of the Crusade amidst the graves of Eldar dead. Thousands of soul-stones had been crushed in the battles between the Legions, their energies feeding the spawn of the Dark Prince while turning His warriors' attention away from the fight and toward the quest for more of the precious gems. The animated constructs of the xenos had been crushed between the two warring Legions, reduced to thin bone dust by the ceramite boots of the Chaos Marines. A handful of living eldars, who had come to the planet for purposes unknown, had similarly died – the lucky ones at the hands of the Imperial Fists, the rest under the fangs of the Blood Angels.

When the Legions had come here, all had known that this would be the final battle. The skies above Iydris had been filled with hundreds of ships, belonging to the two Legions and their allied warbands. Titans had fought Titans, and the allegiances of hundreds of warriors had suddenly shifted as the other side made them a better offer. Not since the collapse of the Eldar empire had the Eye seen such a confrontation, but the troops gathered were but the paler aspect of the war being waged here.

The two Primarchs had left their homeworlds in person to confront each other, and the sheer scale of such a fight would force both sides to retreat to lick their wounds once it was done, regardless of who would claim victory – if anyone could do such a thing, here in Hell.

Organization

The Excoriators
In the aftermath of the Legion's breaking, some Imperial Fists were unable to accept their double failure. They began to ritually spill their own blood in self-flagellation rituals and more elaborate tortures, seeking the forgiveness of the War God. The constant pain they inflict on themselves has unhinged their minds, making them insensible to wounds taken on the battlefield and obsessed with victory at any cost. They are pariahs amongst the Seventh Legion because of that, for they care nothing about honor. While a completely different breed than the Sword Brethren, they are no less deadly. When Sword Brethren may display some twisted form of chivalry, the Excoriators do not.

Before the Heresy, Dorn's command over the Imperial Fists was unquestionable and unquestioned. His word was law, and those who carried his favor were the only true authority above individual Companies Captains. Even when they renounced their loyalty to the Emperor, the Fists kept their old hierarchy, though it began to weaken as Khorne's hold on their souls strengthened. However, after the Blood Crusade and the sealing of their pact, the discipline of the Legion was reaffirmed, only to be shattered forever at the Breaking.

Now, ten millenia after their founding, the Imperial Fists no longer have anything resembling a command structure. Most of them fight under the command of warlords of other Legions, acting as shock troopers and champions. A few, calling themselves the Knights of Dorn, still attend their Daemon Primarch on the Legion's new homeworld. Only on rare occasions do the Seventh act with united purpose, but these occurrences have each caused terrible damage to the Imperium. These Blood Crusades inevitably collapse when the ego and paranoia of the Imperial Fists lead them down their own paths, even when Dorn himself leads his sons to war. The First War for Armageddon was the last such incursion, with Dorn's summoning and subsequent banishment causing it to end.

Warbands of Imperial Fists tend to include very few Astartes, instead relying upon armies of mortals better trained and disciplined than most Chaos rabble. The leaders of such groups drape themselves in all manners of self-aggrandizing titles, some of them based on the old Legion's hierarchy, others issued by daemons from languages never meant for the human tongue.

The Blood Crusades
The Pact of Blood (M30) : During the Heresy, the Imperial Fists rampage across Segmentum Obscurus, slaying billions of Imperial citizens to seal their Primarch's pact with the Blood God. To this day, the echoes of the slain's dying screams still resonate in the Segmentum, and occasional Warp Storms erupt when innocent blood is shed in great amounts.
The War of Woe (M31) : Inside the Eye of Terror, Dorn gathers a great part of his Legion to wage war against his brother Sanguinius, whose patron power, Slaanesh, stands in opposition to Dorn's own hateful deity. The war never really stops, though the Blood Crusade itself ends after the two Daemon Primarchs fight each other on the daemon world of Iydris.
The Battle for Skalathrax (M32) : Demetrius Katafalque, one of the first Excoriators, leads an assault on one of the Twelfth Legion's recruiting worlds. Angron, Primarch of the World Eaters, fight against a horde of Khornate cultists and Chaos Marines for several weeks with a handful of his warriors until the Emperor's Children, led by Fulgrim himself, come to their aid.
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The Curtain of Blood (M36) : Dozens of individual warbands of the Seventh Legion emerge from the Eye of Terror through newly opened paths in the Empyrean. Bypassing the Iron Cage, they lay waste to dozens of Imperial worlds, drawing to them important contingents of loyal Astartes and easing the rise of the Age of Apostasy.
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The War for Armageddon (M41.5) : With the help of Logan Grimnar of the Space Wolves, Rogal Dorn is summoned on Armageddon. It takes a combined effort of the World Eaters and the mysterious Grey Knights to defeat the forces of the Blood God and banish the Daemon Primarch.

Homeworld

In the Eye of Terror, Dorn claimed one of the many worlds of the fallen Eldar empire as his Legion's new base. Before the first battle of the Iron Cage, Imperial seers that peered into the Eye to watch the Traitor Legions described it as a giant fortress, with daemon engines capable of shooting approaching ships and walls higher than those of the Imperial Palace, taking advantage of the fluctuating nature of Eyespace. The will of the Primarch was more than capable of shaping a daemon world according to his whims, and the planetary fortress he created was one of the greatest strongholds in the Eye. This, however, changed after the Breaking and Rogal Dorn's ascension to daemonhood. His rage at being defeated by Perturabo on the field, and then betrayed by his closest son, could never be appeased. Gone was the willpower that had turned an entire world into the ultimate fortress : instead, a wasteland of volcanoes and rivers of boiling blood formed. For several centuries it remained it so, until at last the fury of the Primarch turned into cold rage : then the daemon world became icy cold, and great storms roared in its infernal skies. Ever since then the cycle has continued, the nature of the Seventh Legion's homeworld changing every time its Daemon Primarch's temper does so.

The interrogation of captives from the Eye of Terror has revealed that the Imperial Fists call the world Esk'Al'Urien, or 'The Fury that never sleeps' in the old tongue of Inwit. Warbands and champions of the Legion build skull altars for the glory of Khorne, not on the world itself but in orbit, creating rings of bone around the world. On the planet, daemon princes and powerful warlords of the Blood God head hosts of hellspawns against each other to please their infernal patron and slake their own thirst for blood.

Beliefs

The Feast of Blades
Once every century, dozens of Imperial Fists warbands gather on their homeworld. Each warband chooses a champion, and they fight to the death. The winner is rewarded with the Dornsblade, a daemonic weapon of staggering power who will always find its way back to the daemonworld in time for the next Feast. It was once wielded by the Primarch himself, but upon his ascension during the Breaking, he lost the ability to use it. Because he carried it with him in the Iron Cage, the blade is a reminder of his defeat, and shimmers with the fury of the Emperor's son. To carry the blade into battle is to expose one's soul to that rage, and even with the blessing of Khorne, most Imperial Fists lose themselves until the carnage is done. With the power of the daemonblade infusing their flesh, they are all but invincible, and their allies stay out of their way lest they attack them in blood-crazed fury.

The Imperial Fists serve Khorne, the Blood God of Chaos, Lord of Skull and Murder. Their corruption took root during the Great Crusade. Then the Imperial Fists sought glory in battle, and to obtain it needed strength of will and arm. They kept old superstitions in their ranks of the gods of war of old, honoring them with their deeds on the battlefield in return for their blessing of might. Yet these were more traditions to help them keep heart in the face of the immensity of their task, rituals of brotherhood in a life where a violent death was the only certitude.

Now, the Imperial Fists have turned their discipline and rigor to the worship of Khorne. To them, the only way to prove their devotion to their patron is on the battlefield. Either through the slaughter of countless enemies or the quest for powerful foes to defeat in single combat, every son of Dorn endeavors to earn the Blood God's favor. Duels to the death are fought amongst them at the slightest affront, be it perceived or real – not out of bloodlust, but out of faith, or perhaps in some case necessity : Imperial Fists who lose the favor of the Blood God quickly succumb to Dorn's Darkness, a genetic curse afflicting all of their bloodline.

'Upon the fields of battle,
With the blood of brother and foe,
We honor the Blood God,
The Lord of Skull, Master of Battle.'
Canticle of the Black Templars

Combat doctrine

Lysander, the Heir of Dorn
For five centuries now, an Imperial Fist known as Darnath Lysander has been the scourge of the Iron Cage around the Eye of Terror. He has led many raids against the Iron Warriors' fortress-worlds, and seems to enjoy the favor of both the Blood God and its Daemon Primarch Rogal Dorn. Inquisitorial personnel has been researching that Chaos Lord for almost as long, and the tale they have been able to piece together is a frightening one indeed.
Lysander was the son of a couple of faithful Imperial citizens, undergoing a pilgrimage to Holy Terra, as billions across the galaxy attempt every year. The transport that carried them, however, came under attack by an Imperial Fist warband led by the Chaos Lord Shardryss. The ship was boarded by Khornate cultists who butchered the defenseless civilians. In spite of his youth, Lysander fought back, and impressed Shardryss enough that he ordered him captured instead of slain. Lysander was then brought to the Eye of Terror, and underwent the soul-crushing agonies of the attentions of the Seventh Legion's Apothecaries. By the time he returned from the Eye of Terror, he was an Imperial Fist body, mind and soul.
The young Chaos Marine fought in the infamous battle of Haddrake Tor, where he killed a Captain of the Thousand Sons who had just killed his warlord in single battle. This propelled him at the head of the warband, and for several decades he raided Imperial positions and other warbands within the Eye.
Then, almost a century after the battle of Haddrake Tor, Lysander was captured by Iron Warrior Warsmith Shon'tu, one of the Keepers of the Iron Cages. Shon'tu wanted to interrogate the Imperial Fists to learn of the current situation in the Eye – something that has been very precious to the Fourth Legion at times. But to his great shame, Lysander managed to escape, and returned to the garrison world of Malodrax with a great force of Chaos renegades fighting under his banner. Shon'tu fought the invasion with every means at his disposal, but was forced to abandon the planet when Lysander unleashed a Bloodthirster of Khorne against his defenses. How exactly the Imperial Fist managed to gain the help of such a potent daemon, none but Lysander and his foul god know.
As a reward for his deed, Lysander was awarded the Fist of Dorn by the Daemon Primarch himself. The weapon is a power fist of awesome power, wielded by Rogal Dorn during the Great Crusade. This has led some Chaos warriors to call him the Heir of Dorn, a title that causes much concern amongst the Inquisition. As a creature of the Warp, Rogal Dorn cannot leave the Eye of Terror for protracted periods of time, but Lysander isn't so constrained. The fear that he may undo Sigismund's Breaking of the Seventh Legion and gathers its tens of thousands of warriors under one banner has kept many an Inquisitor Lord and Warsmith awake at night.

Most of the time, Imperial Fists seen by the Imperium are fighting for other warlords, playing whatever role their commander demands of them. Seventh Legion's warbands mostly operate in small groups of less than a hundred warriors – generally formed of the remnants of an old Company, kept together by the charisma and skill of their leader. These groups go from one battlefield to the next, joining whatever side they choose or targeting worthy foes. Each squad is then given specific orders and unleashed, given free range as to how they are to accomplish their objectives. During the Blood Crusade, when thousands of Imperial Fists gather to wage war, this hierarchy is added another layer between the warbands' commanders and the Crusade's own lord.

Prior to the Heresy, the Imperial Fists were noted as using far more assault squads than other Legions. The units were the vanguard of the rest of the Legion, tasked with breaking enemy lines and securing positions for their brothers to reinforce them. The life expectancy of those warriors was low, and it is believed that it was amongst them that the first signs of Khornate worship appeared. For these warriors, a legacy could only be created through heroic deeds that would be told by the Legion for eternity, and so they sought glory in battle more than most. It is these Legionaries who have become the dreaded Sword Brethren of the Seventh Legion : swordsmen of consummate skill, whose only concerns are victory and glory in the eyes of their hateful god and their comrades-in-arms.

The Seventh Legion is also one of those with the most Terminators in its ranks. During the Great Crusade, they took part in the research that ultimately led to the first models of Tactical Dreadnought Armor, and on Isstvan V, they were the only Legion to be equipped with the devastating assault cannons that had been invented by the Mechanicum traitor allies. Even now, a disproportionate part of Chaos Terminators carry Dorn's gene-seed in them, even if they no longer bear his Legion's colors.

Both of these distinctions are seen in the form of war that the Seventh Legion has become most infamous for : void warfare. As Dorn did when defending the Inwit Cluster from the depredations of the Ork, the Imperial Fists are expert at fleet maneuvers and boarding actions. Those most gifted in it – the dreaded fleetmasters of the Seventh – are often employed as shipmasters by other Traitor Legions, or even take over the ships of human renegades to become corsairs whose name is whispered in fear across entire sectors. On more than one occasion have the Imperial Fists clashed with the Emperor's Children in space battles, matching their skills at boarding actions.

The Curse of Armageddon
The industrial world of Armageddon was the theater of the last recorded Blood Crusades, fought by the Imperial Fists alongside elements of the Space Wolves. During that terrible conflict, the Daemon Primarch Rogal Dorn was brought forth from the Warp by the Space Wolves' psykers. The war against the Traitors was terrible indeed, and victory was only secured for the Imperium through the ultimate sacrifice of almost an entire company of Grey Knights. The holy warriors banished the Daemon Primarch, but Dorn's spite wouldn't let it be the end. Even as his physical form dissolved and his blackened soul was cast back into the hells from whence it came, Dorn cursed the world of Armageddon forevermore. The nature of that curse is the object of much speculation from the Ordo Malleus, but its effects are plain for all to see : in the decades that have followed, the world of Armageddon has been subject to more raids and invasions that most other Imperial worlds, especially those as heavily protected as it is. Even now, the world suffers in the throes of war against the mighty Waaagh ! of Warboss Ghazghkull Thraka, perhaps the most powerful xenos warlord ever encountered in the Imperium's long and bloody history.

Recruitment and Geneseed

The Imperial Fists do very little recruiting since their exile in the Eye due to lack of proper subjects. During the Blood Crusades, what few Apothecaries the Legion still has gather as many children as possible for implantation. These keepers of the Legion's future live in isolated laboratories in the Eye, protected by the full might of what remains of the Seventh Legion. There they inflict torturous trials on their aspirants, breaking their minds and filling it with Chaos heresies. The form of Khornate worship followed by the Seventh Legion is taught to the initiates through being made to fight against daemons once the transformation is all but complete. The Neverborn, bound into the service of the Apothecaries by blood pacts, take the form of many of the horrors that lurk in the galaxy, and the aspirant is forced to fight until he sees the truth that Rogal Dorn himself saw as he fought against the Orks in the Inwit Cluster : that only through strength of arm and will can Humanity endure in the galaxy.

Once the transformation is complete, the new Chaos Marines serve the Apothecary as guardians of his laboratory alongside the Legionaries who have taken up that duty, until a warband with a need for new members and the means to pay their creator for his services arrive. These transactions always take place under the watch of the warriors of the Seventh, and only Astartes of Dorn's gene-line can make them – for since the Legion Wars broke out, only they know the location of the Imperial Fists' genetic facilities in the Eye.

Dorn's Darkness
During the Heresy, Rogal Dorn made a pact with the Chaos God Khorne. In return for an offering of blood unprecedented in the long and bloody history of the galaxy, the Lord of Skull blessed all scions of Dorn with his favor, protecting them from the mindless rage that threatened to consume them all. But that protection can be lost if an Imperial Fist shows cowardice on the battlefield, or similarly dishonors himself in the eyes of the mad God of Blood.
Those of the Imperial Fists who have lost the favor of Khorne plunge into the Darkness. With the protection of the Blood God retired, they are consumed by the same bloodlust that now inhabits their Primarch – and without his strength of will, they cannot hope to resist it. Most of them are killed after their first butchering spree, but a few are captured instead, and kept as last-recourse weapons by sadistic or desperate warlords. Their only goal is carnage, the spilling of as much blood as possible as quickly as possible. Some have been observed to fall on their own blades when without any other victim.

Warcry

The warcries of the Imperial Fists vary perhaps more than in any other Traitor Legion. Most of the time, they shout out their own name or that of their commander, but a few still use 'For Dorn !' in honor of their Primarch. Others instead praise Khorne with the usual battlecries of the Blood God's followers, with some variations, like 'Blood for the Primarch ! Skulls for the Seventh !'

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AN : Longest chapter yet ! Gods of the Warp, that one was long to write. Sorry for the delay, but I had some exams to take care of. Now, though, I am going to have more free time in the coming weeks, so expect another publication shortly. I will probably do a short story first, then return to the Forsaken Sons.

Concerning this chapter, yes, I made Sigismund a villain. No, I am not going to reveal how he survived the wrath of Dorn when just in front of the Daemon Primarch, primarily because I have no idea. Teleportation, probably ? Or perhaps the intervention of Khorne. In both cases, you can understand why Rogal wouldn't want anyone else to know.

There had been several reviews expressing interest for the concept of a End Times series in the Roboutian Heresy. While the idea is also dear to me, it will have to wait until I have completed the Roboutian Heresy, which will take a looooong time. I still have twelve Index Astartes to do, after all, so it will probably be a year at the current rate before it is completed. Especially since the next chapter, the Night Lords, has been expected for a long time. I really don't want to mess this one up, so I will take my time to make the Angels of Nostramo's backstory something as well-written as they deserve.

As usual, thanks for those who have taken the time to review the previous chapters. If you see something incoherent with the previous chapters that I will need to blame on the Alpha Legion, have some idea for what's to come or for a short story, or just want to tell me what you think of this, please review !

Zahariel out.