The Leonine Heresy

by Sharrowkyn

Inspired by the Roboutian Heresy, this is the tale of Lion El'Jonson's fall to Chaos as he leads half of his brothers (and not necessarily the ones you might think) in rebellion against the Emperor. All Index Astartes entries have been completed, and now we are journeying through the various War Zones of the 41st Millennium.

6. Index Astartes: Sons of Horus

Chapter 6: Index Astartes- Sons of Horus

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Index Astartes- Sons of Horus: The Warmaster's Spear

There is no legion with stronger bonds of kinship than the Sons of Horus. The Sixteenth Legion are a brotherhood joined by tradition and honor, and have fought for the Emperor on more battlefields than any other. Few would disagree that Horus Lupercal was the best and brightest of all the primarchs, and his Sons bring honor to his name with every victory obtained and every foe they cast down. Yet the brightest star casts the longest shadow, and the legion has struggled with controlling their temper, just as their father did so long ago. Though the true Warmaster was lost during the Scouring, his legacy lives on with every new Warmaster named, and every victory the brave defenders of man gain for the Imperium is dedicated to the memory of the greatest of generals.

Origins: "Call off your Wolves!"

Though they have borne many names over the years, one appellation has remained with the Sixteenth Legion longer than any other: the Wolves. Many believe this title is in reference to the famously close bonds of teamwork which the legion is known for, but the true origin of the name is quite different. In the latter half of M30, a figure calling himself the Emperor emerged on the war-torn cradle of Mankind. He swiftly conquered the planet, casting down the petty tyrants and abominations which stood against him. At his side were legions of fighters known as the Thunder Warriors, who gave their lives for the Emperor at the Battle of Mount Ararat. In their place, the Emperor used his unrivaled brilliance to create the beings known as the Primarchs, as well as a new breed of superhumans known as Astartes.

The Astartes were unparalleled warriors, designed to forge an empire in a Great Crusade from the disparate and scattered worlds of Mankind throughout the galaxy. Armed with powerful weapons and genius tactics, they were soldiers designed to wage war on a new level, and none could withstand their might. The Astartes were divided into groups known as legions, and it is said the only thing that could defeat a legion of Astartes was another legion, but such theories would surely never be tested. The initial legions were much smaller than those that exist today, with great care put into selecting the initial recruits, and it is no wonder many of these early Astartes went on to gain positions of prominence in the future. However, such small groups would never be able to effectively conquer the stars in any reasonable amount of time, and so their numbers needed to be increased.

Though the Emperor was a master of genetic alchemy, he could not lead the Great Crusade if he was kept in his lab supervising the creation of new Astartes. Therefore he needed facilities and experts that could do so in his place, and for that he looked up to Luna. Terra's Moon has long captivated the imagination of Mankind, and it was the first location settled when humanity took to the stars. It passed through the hands of many rulers over the millennia, and by the latter years of M30, it was controlled by the Selenar Gene-Cults, who had built vast cloning and genetic research facilities across the surface of Luna.

The Selenar Gene-Cultists were a proud people, and would not give up their domain without a fight. Luna had once borne a beautiful biosphere, but the ravages of the Age of Strife had ruined that capacity and rendered the atmosphere thin and unsuitable for human life. Thus the Emperor turned to his Astartes, and sent a single company, five hundred Space Marines, to pacify Luna. The Gene-Cultists laughed at such a paltry force, but their mockery turned to begging when the company tore through their defenses and genetic chimeras like they were nothing. Within a day, desperate transmissions were sent back to Terra, begging the Emperor to 'call off (his) Wolves'. In honor of their great victory, the company gained the title of 'Luna Wolves', and were the first to gain a name of their own.

With the Pacification of Luna completed, mass production of Astartes could begin, and the Luna Wolves rapidly grew in size. They won victory after victory clearing the Solar System of hostile powers. The Age of Strife had cut off many worlds, and Mankind came under attack from within and without. The Sixteenth Legion gained a reputation for ruthless efficiency, utilizing precise strikes aimed at enemy command structures. By eliminating leaders, xenos rabble would flee and defiant humans would surrender to the white-armored giants. The culture of the legion was to change, however, with the return of their genefather, Horus, the First-Found.

Cthonia: The First-Found

As powerful as he was, the Emperor could not be everywhere at once. Nor could he afford to turn over the might of his armies to mere mortals who would die long before the Crusade was concluded. In order to address these shortcomings, the Emperor created twenty sons, each incredibly powerful and possessing genius-level intellects. They were as far above Astartes as Astartes were to mortals, but before they could grow and take their place at their father's side, they were stolen. Whether by accident or treachery is unknown, but the Emperor's laboratories deep beneath the Himalazians were assaulted, and the pods bearing the primarchs were cast to the Warp, sent beyond the Emperor's immediate reach. One of these pods, bearing the High Gothic numeral XVI, came to rest on a feral world known as Cthonia.

Within reach of Terra even without Warp drives, the world of Cthonia was an ancient and dying realm. Exploited for its mineral wealth for tens of thousands of years, its once proud hives were decaying, ruled by savage gangs who fought over territory as they slaughtered each other like animals. No regard was given to culture or progress, and barely a billion people eked out their pitiful existence without any hope of change. The gangs had developed their own identities, each savagely independent, though they occasionally came together to assault the Martian Expeditionary Camps, in hopes of stealing something valuable from the tech-priests who scavenged their world like vultures. It is to such a crumbling and dying world that the primarch who would one day inspire Men across the galaxy came to land.

The figure who emerged from Pod XVI was unlike the figure of legend the Imperium would come to know. He was a small boy, thin and scrawny, and he was taken in one of the many gangs that roamed Cthonia, for abandoned children were a common sight. He quickly learned the ways of his gang, and made many friends among the other children, and his straight black hair was braided in the sidelock style of youth that was fashionable among his people. Children of Cthonia did not gain names until their tenth year, and so he went nameless, just one child among many. He fought, he laughed, he learned like any other child, until the day of the Golden Sun.

The feral people of Cthonia had long forgotten any mastery of space-faring technology, and even aircraft were a rare sight, utilized only by the forces of Mars who scavenged the world for relics of the past. Thus when a vast golden object filled the sky, the people were amazed, and the gangs ceased fighting as they gathered to view this mysterious ship so unlike the bulky landing craft of the Martians. A large crowd surrounded the craft as it landed, who marveled as out marched armored warriors and a being wreathed in gold, who strode through the amazed adults to the packs of children beyond. The golden man knelt before the nameless child, and to the boy's surprise, he hugged him. The Emperor had found his son.

The people of Cthonia recognized strength when they saw it, and such a display of familial affection touched even their hardened hearts. The Emperor announced to all that this boy was his son Horus, and the people of Cthonia knelt before their new master. As he moved to bring Horus onto his ship, the boy tugged at his hand, asking his father if he could bring his friends. The Emperor smiled, and assured Horus that his friends would be with him for a long time to come. Thus the flagship of the Master of Mankind was filled with gangs of children, journeying back to Terra while other forces remained to make a compliant world out of Cthonia.

Horus was only four years of age when his father found him on a world so close to Terra, and like all children, he was filled with questions. His father indulged him, answering all that he could, telling Horus of his grand plans as well as the brothers he would meet as soon as they could be found. Horus was taken to a set of quarters high in the Imperial Palace where he could see the vastness of the world below him, and there he was raised. For three years, Horus thrived under the care of his tutors, learning how to govern a world as well as how to take one. He absorbed knowledge like a sponge, and all who met him were impressed, even the stoic Custodes. The Emperor visited him as much as he could, but the Great Crusade took him away from Terra often, and so Horus wished he could spend more time with his father. Unknown to Horus, the many children of Cthonia who came with him were taken to Luna, and there they underwent the trials to become fully-fledged Astartes, implanted with the gene-seed of the Sixteenth, becoming the new core of the Luna Wolves.

By 799 M30, Horus was seven years of age, still but a child in stature. Being a child, he could of course not lead an army, nor earn the respect of men as an equal. The Emperor had just returned from a particularly grueling campaign against a race of xenos of the False World of Sedna alongside the might of eight Legions. Horus begged his father to bring him along so that he may prove himself a man. The Emperor tried to reason with him, but Horus was insistent. With a heavy heart, the Emperor brought his son deep below the Palace, escorted by but a single Custodian Guard, unremarkable save for a trinket with a twisting serpentine thunderbolt on it. Horus was brought to the Emperor's own gene-labs, where Malcador the Sigillite awaited them. Horus never had much interaction with the mysterious old man, but the few times he had had given him the distinct impression the Sigillite did not like him.

Horus stood alone in the center of the room, clad in a simple brown robe. All around him he could hear the sound of Gellar Field generators. The three other men in the room, if you could call them men, were utterly silent. Horus fought to suppress a shiver, forcing himself to remain still as his father stood concentrating before him.

"I am ready, father. I'll do whatever it takes to be by your side." Horus all but shouted. The Emperor gave him a sad smile.

"I know you will. You are my son, and that's all you need to be for me to be well-pleased." The Emperor's eyes began to glow, and he raised his hand, placing his palm on Horus's forehead. Horus felt a pulse of golden energy radiate from his father's hand, surging into him with the strength of a sun. Horus began to scream.

The Emperor's golden energy suffused the body of the young primarch, and the small body of the boy began to grow even as his robe turned white from the light. Years of growth passed in the space of seconds, and the child became a teenager, then a man, then a demigod. By the time the Emperor lifted his hand, the full majesty of a primarch lay before him, his once-childish face now glabrous and stern. Even unconscious, Horus now radiated authority and power, and the psychically-attuned eyes of the three others in the room beheld a golden-white light limning his sleeping frame. When Horus awoke, he was once more in his chambers. It took him some time to become accustomed to his new body: his strength was unparalleled, and his mind raced at speeds that dwarfed his former intellect. Where once he struggled in combat against the lowliest servitor, now he found himself overcoming even the redoubtable Custodes. Horus was now a demigod, and his father presented him with a suit of brilliant white armor before taking him to Luna. There he was reunited with his sons, and to his delight he saw many of his friends from Cthonia had survived their training. The Luna Wolves were now ready to take to the stars and join the Great Crusade.

Great Crusade: Horus Rising

Horus took to the stars alongside his father, fighting to spread the Imperium of Man from the tiny confines of the Solar System across the galaxy. At his side were the Luna Wolves, the Sixteenth Legion who bore his gene-seed. Together they were unstoppable, and in the span of two decades they had carved out the borders of Segmentum Solar. None could stand before them: the Aeldari were still reeling from the collapse of their Empire, and most other xenos races were too disunited to put up much resistance. Horus and his Wolves were ruthless and effective, and they mastered the art of war like few others.

Despite their undeniable skill in combat, it was diplomacy where the Luna Wolves truly shined. What records remain of their exploits during the Great Crusade indicate for every world they took by force, seven or eight were won over peacefully. It seemed as though Horus had inherited his father's ability to be all things to all people. To the downtrodden, Horus was the voice of sympathy, listening to their plight and winning them to his cause. To the mighty, Horus was a beacon of strength, someone they could kneel before without losing face. To the foe, Horus was destruction incarnate: even the wretched greenskins who were brave to the point of stupidity feared the might of the Luna Wolves, and many orks fled at the mere sight of the famous black and white armor of the Sixteenth Legion. His sons were consummate warriors who enjoyed the thrill of combat, and forged incredible bonds of brotherhood, and none exemplified this more than the Mournival.

Mournival

Horus had long sought to be a wise ruler, and to this end, he established a group of advisors from the ranks of his sons. Named after an ancient Franc phrase from a card game, the Mournival were a group of four, one of each kind of the humors and each bearing a moon above their right eye. It was thought that these four balanced each other out, and thereby the rest of the legion when they provided rational guidance to their father.

To ensure his advisors were well-rounded, Horus selected those who would be good counterbalances to each other and unafraid to tell him the truth so that he might receive all types of wisdom. Any vacant positions were filled by those bearing the proper temperaments, and their membership changed as their bearers died as the Great Crusade progressed. By the end of the 30th Millennium, the Mournival's members consisted of Tarik Torgaddon the sanguine jokester; "Little Horus" Aximand the loyal melancholic; the choleric First Captain Ezekyle Abaddon, who had retained his position the longest; and Hastur Sejanus, Horus's favored son who was said to have a perfect balance of all four humors despite being nominally phlegmatic.

For twenty years, Horus was the sole primarch, an only child who enjoyed his father's attention and friendship as they crusaded together. However, this could not last, and in 819.M30, two decades after they had begun the Great Crusade in earnest, the Emperor called Horus to his side, for he had found another son. Horus left his sons to continue the Crusade in his absence as he eagerly journeyed to join his father's fleet, to the north of Terra on an icy death world named Fenris. There he found his father within a primitive wooden hall, pitiful compared to the hives of Terra, with his arm around the shoulders of a man who towered over the other men in the hall. The man looked over at Horus, and strode up until they were face to face, and sniffed Horus. The man was several inches shorter than Horus, with tangled unkempt blond hair, and stank of alcohol. He began to make a strange noise, barking in his heathen tongue, and Horus realized the man, his brother, was laughing.

The Emperor introduced Horus to the man, whom he called Leman Russ. Russ spoke haltingly in Gothic to him, though his accent made it difficult to understand. Horus was polite to his brother, though internally he was repulsed by this brother's savagery. The two traveled back to Terra, and to his surprise, Russ seemed to regard him as a friend, challenging him to brawls and drinking contests. By the time they reached the Throneworld, Horus found himself beginning to like this brother. Horus helped train Russ in the Imperial methods of warfare, and Russ joined the Emperor and him as they continued the Great Crusade.

Decades passed, and more brothers began to turn up, from / =][= FILE DELETED =][= / around five years after Russ, to the final-found Alpharius over a hundred and fifty years later. Horus was by the Emperor's side when many of the primarchs were found, and all found themselves looking up to their eldest sibling. Almost all of his brothers fought by the Emperor's side when they were initially found, but many of them then chose to come fight by Horus's side afterwards until their legions were big enough to campaign on their own. In this time, the Luna Wolves continued to rack up victory after victory, and no legion could rival their brilliance. Several brothers began to grumble against Horus, jealous of his successes, but despite this, none truly grudged him, for his charisma was unmatched. Even unruly Angron or proud Guilliman listened when Horus spoke. His sole failure was with Corvus Corax, whose abrupt departure after a difficult campaign bothered Horus.

Despite this lone setback, Horus fought alongside each and every one of his brothers, getting to know both them as well as their legions. By the end of M30, all of the other primarchs had been found, and Horus was the brightest of them all. He knew how to utilize them to the best of their abilities, and was generous with the credit. Each and every foe was crushed before his might, from vast ork empires to Aeldari craftworlds to rival human empires; the only threat they did not face were the Rangda, held at bay by other legions, though Horus was well aware of their dread reputation. Horus's greatest success came at the turn of the new millennium in M31 with the Ullanor Crusade. For several years, the Luna Wolves had clashed with the forces of Urlakk Urg, Warboss of the largest recorded Ork Empire in history, whose sheer numbers gave even the mighty XVI pause. Horus called upon his brothers for aid, and forces from the Iron Warriors and Star Hunters responded. Together, the three legions comprising over two hundred and fifty thousand Astartes as well as billions of mortal troops drove deep into the defensive lines of the xenos.

Despite such a monumental force, the orks were simply too numerous, and Horus found himself isolated with only a company of his sons for support upon Ullanor itself after a failed speartip operation. He prepared to go down fighting, surrounded on all sides, when a brilliant golden light shattered the sky above the teeming hordes. The Emperor of Mankind himself had arrived to aid his son in battle, and at his side were a thousand of his elite Custodians. The forces of Man rallied to their leader, and Horus fought back-to-back with his father as they slaughtered their way through the greenskin masses. Together they ascended the tower which held the Orkish warboss Urlakk, and Horus slew him in single combat, casting his broken body down into the panicked mob below. The orks were routed, and began fleeing the system in vast numbers.

For such a victory, the Emperor lauded his son, and called for a victory triumph in his honor. Summons were sent throughout the galaxy, calling the greatest heroes and most important dignitaries from across the Imperium to come pay tribute on this glorious occasion. Horus protested such honors, for he would have surely perished without his father's intervention. The Emperor reassured Horus, and after months of preparation as entire continents were flattened, the Triumph of Ullanor was held. Never before had there been such a magnificent show of Imperial force and might, and never would its like be seen again. Ullanor was declared to be a Trophy World, the only one of its kind, and millions of Imperial Army soldiers, hundreds of thousands of Astartes, and hundreds of Titans of all classes marched across its vast parade grounds. All facets of the mighty Imperial warmachine were represented, and those who had personally fought received the right to wear the Ullanor Triumph Bar.

At the head of the parade grounds lay a massive golden fortress, whose walls were guarded by the Custodes. On the highest balcony supervising the parade stood the Emperor himself, and at his right hand stood Horus. Beside them stood eight of his brothers, yet the place of honor was unmistakably Horus's. As endless waves of Imperial aircraft flew overhead, Horus knelt before his father, who placed a laurel wreath upon his head, naming him Warmaster. Horus accepted his title with grace, and swore to prove a worthy successor and faithfully carry out his father's Crusade.

As his brothers rushed to embrace Horus, the Emperor made a more personal announcement to the nine sons gathered there. He spoke to them softly in a low voice that only they could hear, and told them he was withdrawing from active leadership in the Great Crusade. Such news was even more shocking than Horus's coronation, and the other primarchs turned their attention to trying to ask their father questions. Horus did not join them in this, for he had discussed these matters with his father many times over the past few months as the Triumph preparations were underway. Finally, the Emperor withdrew, and Horus was left with his brothers and the weight of his crown.

False Gods: The Warmaster Supreme

Such concerns would have to wait though, for now was a time of celebration. All of Horus's brothers there congratulated him, and they held a private feast as the rest of the Imperial Forces prepared to withdraw off-world. Within a small room, the nine demigods sat together, Horus at the head and his brothers on both sides. His brothers began to discuss the future of the Crusade, and the topic turned to the idea of renaming Horus's legion now that he was Warmaster. Magnus the Red suggested they be called the Sons of the Eye, while Lorgar suggested they be called the Wolves of Horus. But it was mercurial Sanguinius, primarch of the Blood Angels, who won the day, combining the suggested ideas into the name 'Sons of Horus'. Horus and his brothers loved the idea, and the order went out. The legion's colors and iconography changed as well, going from white and black to a pale green and black, with the Eye of Horus upon their shoulders.

Horus had initially refused the mantle of Warmaster, but the Emperor had convinced him of the necessity of a strong leader in his absence. The Great Crusade needed to continue, its legacy cemented. The forces of the Dark Angels had just completed the destruction of the Rangda in the Third Rangdan Xenocides, while other legions had seen to the scattering of the last known concentration of orks within the Ullanor System itself. However, many worlds were only loosely compliant, and a close eye would need to be kept on them. Astartes would make poor tools for maintaining compliance, as fear and hate would only drive planets to simmering discontent and eventually rebellion should worlds believe they have an opportunity to cast off their yokes. Horus and the Emperor had discussed this issue many times in the months leading up to the Triumph, and thus when it came time for Horus to begin acting in his new role, the first order he gave was to establish the Twin Corps.

Iterators and Remembrancers

The Imperium had gone from victory to victory, but now stood the daunting task of keeping it. Mortal men and women were who the Imperium was designed for, and thus they would take part in securing the Imperial Legacy. Personally selected by Malcador the Sigillite, the Iterators were orators and sophists, historians and rhetoricians, the creative minds who were one in a hundred thousand. Closely accompanying them were the Remembrancers, artists of every sort, whose works would inspire the vast and diverse populace. Together, these two orders would convince the common people of the benefits of being in the Imperium, stirring up their loyalty and keeping them invested.

At least, that was the public explanation. Those with a more cynical outlook believe the twin orders were but mouths for propaganda, spreading the Imperial Truth by dishonest means. Decades earlier, the primarch Lorgar had preached the divinity of his father, and though he had since ceased, worship of the 'God-Emperor' was still prevalent on many backwater worlds. The Iterators were specifically trained to refute these beliefs, and many of their first assignments were to worlds once visited by the Word Bearers.

Despite being named Warmaster, it would be quite some time before Horus and his Sons would see war again. Before he had departed, the Emperor had told his assembled sons that he intended to call a general council, and that the primarchs would be expected to be in attendance. Horus was one of the few who were privileged to know the purpose of this council: to rule once and for all on the question of psykers in the Astartes legions. Horus had supported his brothers' Librarius project, and planned on speaking in favor, but now as Warmaster, he felt he needed to be impartial, and allow his brothers to convince their father one way or another.

Thus when the Council came to order many months later, Horus was in attendance. In that time, he had traveled from brother to brother, testing their obedience and loyalty by asking them to contribute a force to his legion. This motley assortment of Astartes would join the Sons of Horus as a new force called the Legion Auxilia. Such a gathering had not been seen since the earliest days of the Great Crusade, when all Astartes had fought as one without their primarchs underneath the Emperor's banner, and so Horus wished to renew these bonds once more. Initially, the Auxilia served merely as soldiers, but at the suggestion from an unlikely source, a senior officer was taken from each group to act as a representative and ambassador for their legions.

This source was none other than Horus's brother, the primarch Lion El'Jonson. The lord of the Dark Angels had never been close to Horus, preferring to keep his own company. Although he was tenth-found, the Master of the First had long been seen as an authority in his own right, a predator without equal, and some even whispered that it should have been Lion named Warmaster. Horus had not seen his brother in decades, for the Dark Angels had been occupied as part of the main thrust against the Rangda near the Ghoul Stars. To Horus's surprise though, the Lion approached him as a brother, even showing him a rare smile that Horus could tell was difficult for him. The First Primarch and the First-Found became closer that day, and Horus was certain this would be the beginning of a new friendship with his brother.

There was a great deal less camaraderie at Nikaea though, and much of Horus's time was spent playing mediator between Rogal Dorn and Perturabo, who almost came to blows over who would get to build the council chambers. His attempt to have them work together to build it ended in disaster, and Horus had to ask Vulkan to fix it at the last minute. When the debates started, Horus watched from his father's side, and during breaks in the discussions, he issued commands as Warmaster. Meeting with each of his brothers individually, he brought them around to his way of thinking, and left them satisfied, if not happy, with his instructions that they would carry out after the Council had ended. Perturabo and Dorn were to both be sent back to their own campaigns, and Horus took care that they would not come into contact with each other. The forces of the Death Guard and Blood Angels were tasked with continuing operations near Chondax, both part of a wider net to quickly and efficiently dispatch the remaining greenskins. At the same time, messages were sent to the wild Jaghatai of Chemos to let loose his Star Hunters upon Chondax itself, the main pocket of orkish resistance.

With these brothers dealt with, Horus turned his attention to those deemed more likely to be a problem. Many of the remaining brothers had not been present on Nikaea or Ullanor, and he had concerns about their willingness to obey. Some were allowed to carry on as before, their loyalty going without question such as Leman Russ or Konrad Curze. However, the brothers which most bothered Horus were Roboute Guilliman and Ferrus Manus. As Horus expected, Guilliman sent only a missive instead of approaching him, a terse request asking to withdraw his forces back to Ultramar, to which Horus agreed, for he sought to soothe his brother's wounded pride. Ferrus Manus had been the fourth-found, a commander of his own sphere of conquest, and some even saw him as being in contention for Warmaster. Horus dealt with him by relaying the commands through his best friend Fulgrim, and thus the Gorgon obeyed.

That left only a few brothers. The mysterious Alpharius had not been seen in many years, so the Lion was acclaimed as Voice of the Warmaster and deputized to deliver Horus's orders personally before doing the same with Angron. Finally came Corvus Corax. Horus tried to mend the rift between them, but it seemed like his brother would not make the same effort. While Horus was busy with orders, the Council of Nikaea came to a close, and he duly disbanded his Librarius in accordance with the decree of the Council. He had been unsure which way the council would decide, and as it had banned the use of psychic powers, he now tasked Lorgar with dispatching Word Bearer chaplains to oversee compliance to the Edict of Observance. In the meantime, Horus worked on assigning the censured Thousand Sons to legions who would watch over them until the time came to reunite the Fifteenth Legion. After the Council of Nikaea ended, Horus attended the ceremony where Vulkan was named Praetorian before returning to his legion, who had been waiting in orbit. Together, they rejoined the Great Crusade, for Horus greatly desired to get away from the politics of the Council back to honest conquest in his father's name.

However, it seemed as though the Warmaster's troubles were only just beginning. Now that he was the head of the Crusade, Horus found himself inundated with requests from all sides. He had thought his brothers would be the main source of trouble, but it was the mortals in their endless numbers that truly dragged him down. He found himself spending all day answering questions and giving new deployment orders in such numbers as to bog down even his superhuman intellect. Most irritating of all were the inane requests coming from Terra. It seemed Vulkan was taking his title of Praetorian of Terra very seriously, and was petitioning Horus and his forces for help in securing tithes to support his building projects. He humored his brother at first, but found this only encouraged others, including a group calling themselves the Council of Terra. Horus tried to reach his father, but found his requests countermanded by Malcador the Sigillite, whose authority as Regent gave him status to do so. Thus Horus found himself having to divert significant portions of his fleet to fulfilling these requests, be they allowing remembrancers to live among the Astartes or to complete a particular conquest. After five years of this, Horus had had enough. He began to route all these tasks through the Mournival, by which time had expanded to become the Mournival Majoris. This twenty-one man council, consisting of the four original members along with the representatives from the other legions, began to handle the paperwork and other mundane tasks, and Horus could finally return to conquest.

Able to pay closer attention to his Sons, the Warmaster discovered they had changed while his focus was elsewhere. Many new Astartes had been recruited in the aftermath of Ullanor, and so Horus found himself a stranger to entire chapters of his own sons, whose culture and practices seemed novel and strange. In the past few years, groups known as Warrior Lodges had begun to spread through his legion. Initially a personal project of the Lion, the Lodges had now grown to make up nearly a quarter of the Sons of Horus, and he suspected they existed in most other legions as well. Though he allowed them to continue to meet, he did not approve of their theatrically secretive nature, and so when he was choosing forces for his return to conquest, he made certain to pick those not part of any lodges. Gathering these most trusted forces, Horus created the Sixty-Third Expeditionary fleet, and began to fight on the battlefield once more.

While Horus fought alongside this elite force, the Mournival Majoris handled the logistics of the rest of the legion, who had been dispersed to conquests elsewhere, handling outside communication and routing Horus's commands through the Voice of the Warmaster. They conquered nearly a score of worlds in quick succession, reminding the doubters why the Sons of Horus were the legion of the Warmaster. Most of these worlds were human-inhabited, but all refused compliance and had to be brought in by force. The worst of these was 63-19. This system was home to an advanced stellar empire in possession of a great deal of archaeotech. Initial negotiations went well, until the discovery that they called their homeworld 'Terra' as well, and insisted that their emperor was the only true leader of humanity. When the inhabitants of 63-19 discovered that the Imperium also believed this, they resorted to war, attempting to assassinate the Imperial delegates. Such a horrific breach of diplomacy resulted in the death of Horus's equerry Maloghurst, whose mangled, twisted body was broadcast to the outraged fleet above. In retaliation, the world was obliterated from orbit by a vengeful Horus. Such swift justice meant they would not be bogged down against an intransigent foe, but it also meant the foe's technologies died with them, which angered the Mechanicum portion of the fleet.

Shortly after this, the 63rd received distress calls from the nearby 140th and 28th Expeditionary fleets. A large detachment of III and IX Legions had been stranded on a world they called "Murder". The 63rd came to their rescue, and joined in the fight against hideous xenos called Megarachnids. No foe could stand up for long against the might of the Warmaster's Legion, and so within six months, they were well on their way to taking the world, though by this time the forces of the IX Legion had perished. However, the campaign was interrupted before it could come to a proper conclusion with the arrival of a new force: the Interex. Envoys from a human civilization, these interlopers revealed that the Imperial forces had been assaulting a nature preserve. Irritated at such a pointless waste of lives, Horus's temper was frayed as he and his forces journeyed to the nearest world of the Interex, a strange planet named Xenobia. There they were horrified to see these humans accepted xenos among their ranks, and the talks quickly broke down. As Horus left the hall where he and his sons had been negotiating yet another fruitless discussion, they came under attack. A mixed group of xenos and humans threw themselves at the Imperial delegates, and began to assault the unarmed negotiators.

Was there something wrong with this area of space, Horus wondered to himself, something that drove these people to reject Imperial Unity? Or perhaps it was the year? Horus did not know if the number 11 was significant or related to treachery, but it was not as if he was very superstitious anyway. Around his feet lay the broken bodies of xenos and humans alike. Horus and his Sons had come unarmed as a display of good faith, but despite this they were still Astartes, and the corpses of their treacherous attackers were testament to Imperial strength. With nothing but their bare fists, the Primarch and his bodyguard tore through their attackers with righteous fury, and not a single Imperial fell.

As Horus wiped the gore off his hands, he felt a sharp pain in his back. Reaching around, he discovered a small wound in the joint gap of his armor near his spine, from which sickly black blood poured forth. Such a wound was unnatural, for the cut itself was miniscule, and he had not even felt it in the heat of combat. Horus tried wiping his eyes as his vision began to swim, and the concerned voices of his sons rang in his ears as he crashed to the ground, unconscious.

Galaxy in Flames: The Death of Unity

As their father fell before their very eyes, the Sons of Horus went mad with grief. They rushed him back to their flagship in orbit, the Vengeful Spirit, and called the rest of the legion to their side. While the Mournival awaited the rest of their brothers' arrival, Horus lay unconscious in his quarters, clearly in great pain. At first only the inner circle knew, but a primarch being seriously wounded is a hard thing to keep secret, and soon the rest of the forces present found out. With righteous fury, the Astartes of the Sixteenth led by Abaddon went to war, throwing aside any thoughts of diplomacy in favor of revenge. Xenobia became an abattoir while up in orbit, the Mournival Majoris met in council, desperately trying to decide what to do. The assembled chapter masters debated many courses of action, listening to the merits of all. The first suggestion came from Ahriman of the Thousand Sons: telling the assembled Astartes that the small yet potent wound reeked of the Warp, and that a Warp-based remedy would surely cure a Warp-based wound. Some agreed with his assessment, but Ahriman lost their favor when he suggested that the Edict of Observance be overturned to facilitate such a cure.

Another suggestion came from Corswain of the Dark Angels. Beloved Corswain, as Torgaddon had jokingly dubbed him, had long been a leading figure among the Mournival Majoris, and many chapters of the Auxilia looked to him for guidance. Corswain suggested seeking the advice of one of the Warmaster's brothers. He insisted that the most logical choice would be the nearest primarch, which just so happened to be his own gene-father, Lion El'Jonson. This suggestion garnered much more support, and nearly half of the assembled chapter masters agreed with him, including Aximand, who voted on behalf of the absent Abaddon. It seemed as though that would be the course taken, when a voice from the back of the room spoke up with another alternative.

Stepping forward, the voice revealed itself to be that of Erebus from the Word Bearers Legion. The High Chaplain pointed out that the Warmaster may well die before the Lion arrived, and that something had to be done in the meantime. Erebus suggested that Horus be interred in a stasis vault lest he succumb to the wound. The Council swiftly agreed, and the Warmaster was placed inside the vault, his face frozen in the rictus of pain it had borne since he fell unconscious. With his condition stabilized, the Mournival Majoris returned to debating where to take him, and the council was split into two factions, one favoring a journey to the Emperor on Terra despite the distance involved, and the other favoring going to the Lion as the closest primarch.

The Council seemed evenly split, with ten members on each side, until the time came for the final vote to be cast. The last to vote was Jago Sevatarian, the legendary First Captain of the Night Lords who was rumored to have the gift of foresight. With a lingering look at Corswain, Sevatarian cast his vote in favor of a journey to Terra. Corswain became agitated at the decision, begging the council to reconsider, but their minds were made up. The Dark Angel demanded to be released to rejoin his Primarch, and the Council allowed it, though not before Sejanus required him to swear an Oath of Moment to keep the matter a secret. Thus as the Dark Angels departed from the Legion Auxilia, the Vengeful Spirit entered the Warp on a journey to Terra.

As soon as they transitioned into the Immaterium, the Vengeful Spirit was hit by the same storms which were plaguing the rest of the legion attempting to reach Interex space. It was as though the storms were sentient, like they were trying to stop them. The Warmaster had received many reports of worsening storms over the past few years, but they were always chalked up to exaggeration. After months of travel, the battered Vengeful Spirit finally transitioned back into realspace. They had suffered multiple breaches in their Gellar Fields, and the forces within found themselves battling with strange monstrous xenos that whispered words of madness as they threw themselves at the chambers containing Horus's stasis vault. After entering the system through the Elysian Gate and making the short journey through the Solar System itself, they arrived at Terra at the Lion's Gate Spaceport, and the vault was rushed down into the depths of the Palace. The Emperor himself went to the medical wing, and through methods unknown, began to heal Horus. The rest of the Sons of Horus were kept on their ship, barred from entering the Palace by the stoic Custodes who guarded the space port so high above the Palace.

While the Mournival attempted to bring Horus back to Terra, the rest of the legion mustered around Xenobia. Led by First Captain Abaddon, the Sons of Horus vented their fury upon the vile assassins and their empire. The Imperial forces found themselves initially outnumbered, barely throwing back attack after attack from vessels bristling with strange armaments that combined human and xenos science to deadly effect. However, despite their technological advantage, the Interex were hard-pressed to repel the Warmaster's legion, especially the Catulan Reaver Squads of the vaunted First Company, masters of boarding actions and the epitome of the Speartip balance of power began to shift in their favor as more legion vessels arrived, only to be taken away by the unexpected withdrawal of the Thousand Sons attached to the fleet as well as nearly half the Legion Auxilia. The disappearance of nearly twenty thousand Astartes and their attendant ships nearly cost the Sons of Horus the war. However, through the heroic actions of the veteran Captain Iacton Qruze, the line was held, and the Interex fleet was broken. The campaign had been won, and the fleet entered the Warp several days later, leaving dozens of Interex worlds as smoldering ruins as they fell back to Terra to learn their father's fate.

Initially, First Captain Abaddon had demanded that the fleet return as soon as the battle had been won, but cooler heads prevailed. Unknown to the Sons of Horus, had they entered immediately, they would have surely been lost, for it was at that moment that the Astronomican flickered. Many ships caught in the Warp at that time found themselves inextricably lost, dragged into the lightless depths of the Immaterium, never to be seen as they were again. The Sons of Horus did not know this, however, and, after struggling through terrible tides even worse than the storms they faced on the way there, made it back to Terra.

When Horus awoke, he found himself in the chambers where he had grown up over two hundred years before. Sitting up, he found Malcador the Sigillite sitting beside him. Even after becoming Warmaster, Horus had never been close with his father's advisor, and had even come to blows with him in the past. The Regent seemed as ageless as ever, and began to tell Horus the kind of news that made him wish he was still unconscious. He sat dumbfounded as Malcador informed him how his brothers had ceased communicating to Terra, forces gone missing, as well as an assault on the Palace itself from Magnus and his Sons. A sense of shame crept over him, as though Horus had been responsible for this…heresy. As Malcador began to leave, Horus called the orderlies to his bedside, and began to issue orders and demands. Even as he lay convalescing, the Imperial war machine began grinding into action, responding to the will of the Warmaster. By the time Horus recovered, his Sons had arrived on Terra and were ready to put the Warmaster's plans into action. The Sixteenth Legion took to the stars, gathering their fleets into one body for the first time in decades. Most legions were dispersed into many groups, but as the Warmaster's legion, the Sons of Horus had split themselves into nearly a hundred separate smaller fleets. Now though, they had returned, mustering above the world of Davin near the galactic core as they waited for their father to make a decision.

Horus sent out missive after missive to his brothers. Many were never answered, while others claimed this was the first they'd heard of anything. Nobody seemed to have any knowledge of where the Thousand Sons had gone, and even the Space Wolves, whom Horus had sent to track them down, began to stop sending updates. The storms continued to intensify, and communication with Terra and other legions became spotty, before ceasing almost entirely, forcing the Warmaster to rely on messengers and other less efficient means. For well over a year the Sons of Horus sat holding their positions, as other parties came and went as they treated with the Warmaster. The silence began to feel deafening, the calm before the storm, as though the galaxy was holding its breath for whatever would happen next. The storm broke with the arrival of the battered Ninth Legion fleet. The Blood Angels had not been heard from since they traveled north to track down the Raven Guard and the World Eaters, and it looked like they'd been through hell. Barely half the number of ships which had set out had returned, and those that had were shells of their former selves. Next came the First Legion fleet. The Lion had been in and out of contact with Horus, carrying missives and messages, but the armada arriving in the Davin system appeared to be the bulk of their fleet, though their true size was, like many things with the Dark Angels, rather unknown, even to the Warmaster.

Horus spoke with his brothers remotely from his ship, learning all that they had to tell him. Lion informed him that Dorn, one of the brothers whose updates had stopped, had been engaged around the Tallarn System and cut off from communications due to Warp storms. However, he also said he had been unable to track down the Star Hunters or Space Wolves. For his part, Sanguinius told him that the World Eaters had gone renegade and nearly destroyed the Raven Guard in their entirety. With tears in his eyes and rage in his heart, Horus proclaimed the Twelfth and Fifteenth Legions to be outlaws, and at the Lion's suggestion, the Fifth and Sixth Legions as well, for their silence was highly suspicious. While the Lion and his fleet moved to the edge of the system to broadcast the Warmaster's Decrees, Horus took a transport down to the surface of Davin to meet with Sanguinius, who wished to speak privately.

Upon the surface of Davin, Horus waited for his brother's arrival in the ruins of a once-great fane. In a forgotten age it had been a site of worship, a grand marble temple standing upon an octagonal foundation, with vast ophidian carvings upon every wall. Compliance at the hands of the Word Bearers had not been kind to Davin, for now the temple and others like it stood abandoned, its devotees fled and the building left in ruins for many years. The far end of the temple lit up with the telltale actinic flare and reek of ozone that signified a teleporter, and stepping out from the light was the Angel himself. Horus was shocked at the state of his brother's appearance: the once proud golden armor was covered in bloodstains and holes; his long hair and magnificent wings looked as though they had been torn and ripped; and his face was covered in scars and stains, especially around his eyes. Horus asked what had happened, and his brother held up a strange bloody object of tangled metal and grisly flesh. With mounting horror and disgust, Horus realized it was the head of their brother, Angron.

Horus pressed Sanguinius for more information, and his brother told such tales of fratricide and betrayal that he would not have believed them coming from someone else. His voice trembling, Sanguinius then went on to speak of maddening rage and uncontrollable bloodlust. Horus had long known of his brother's condition, for he had once witnessed Sanguinius mercy-killing one of his own sons in the distant past, and so he tried to console him. However, Sanguinius only grew more agitated, speaking madness about 'Warp beings' assaulting his ship that whispered temptation and urged excess.

"What are you talking about? You need to calm down." Horus tried to put his hand on his brother's shoulder, only to be thrown backwards, smashing through a ruined pillar. Sanguinius howled, an unearthly noise that no man should have been able to make, and twin red streams began to trickle from his eyes. Horus rolled to one side as the pillar upon which he had been leaning disappeared in a cloud of dust and rubble as his brother plowed into it.

Horus began desperately dodging the maddened blows of his brother left and right as Sanguinius attempted to murder him. Though he was wearing his armor, he did not trust it to hold for long against the Angel's savage blows. In his hand he held his maul Worldbreaker, hesitating to use it against his own brother, even if he had gone mad; it was powerful, but it would not exactly be of much help in making Sanguinius calm down. Even as he thought this, Horus paid the price for his distraction, smashed backwards once more by his brother's mighty wings. His chest was now soaked in blood, though most of it was not his own.

"Enough of this." Horus grunted, annoyed. Swinging Worldbreaker like a bat, Horus connected with his brother's frenzied leap, crumpling the plastron as Sanguinius was sent hurtling backwards, crashing through a half-broken wall. With room to breathe, Horus tapped the teleport homer contained within his belt, a nifty relic from the Dark Age of Technology given to him by Ferrus, before activating his vox.

"Horus to Vengeful Spirit, get me out of here." Bright actinic flares flashed, and when they disappeared, so had Horus, whisked away from Davin and leaving Sanguinius alone in the temple.

Horus found himself once more within the teleportarium chambers of his flagship. Ignoring the confused questions of his sons, the Warmaster rushed to the bridge. There he beheld a vision of treachery: the ragged Blood Angels fleet, which had once been scattered and drifting, had now moved into attack formation. Already, several smaller vessels had been gutted, surrounded and boarded by companies of the Ninth Legion. Horus wasted no time, and gave the order to fire back. Enraged by this unprovoked attack, the Sons of Horus did not hesitate, firing upon those who had once been as brothers.

Many ships on both sides were lost that day. The two fleets were barely a few hundred kilometers apart, knife-fighting range for starships. Vox calls for aid were sent to the Dark Angels fleet out on the outskirts of the system, and the Lion swore he would come to destroy his foe. The Sons of Horus tried to pull back, unable to turn their vessels for a full broadside lest they be boarded by their Blood Angels foes. Several ships who had gotten too close had been crippled within minutes, the length of their vessels studded with boarding torpedoes which had released their maddened cargo like frenzon from a hyperstim. After what felt like a lifetime, the bridge crew signaled that the Dark Angels had arrived. Auxpexes showed their fleet moving into position behind the Ninth Legion fleet, which was now surrounded. The Sons of Horus had finally created a gap in the lines, falling back from the Blood Angels' furious charge, and now with two fleets, the battle was surely theirs. With the arrival of the second wave, the Sons of Horus turned over their engine power to weapons, preparing to annihilate the Blood Angels in one salvo. Yet before they could fire, the First Legion struck. Ship-borne plasma weapons of incredible potency reached out, relics from the Dark Age which the First Legion had long hoarded, knifed through the darkness of space. For those few seconds, it was as though the galaxy held its breath, waiting for the deadly salvo to reach its target.

Not one struck the Blood Angels fleet. In that moment, Horus's eyes widened as he realized the implications. They had been betrayed again. Horus shouted for his vessels to break away, but it was too late. Searing plasma burned its way through the void shields of the Sixteenth Legion, and seconds after, shells from macrocannons, cleverly hidden in the darkness of space behind the blinding light of the plasma, struck the now-exposed hulls of the Sixteenth Legion vessels. In one stroke, dozens of ships were crippled, and losses now totaled nearly a third of the fleet. The Blood Angels ships, which had been silent up to this point, now roared back into action, accelerating to close the gap.

Their lines in utter disarray, the Sons of Horus began to fall back, moving away from Davin to the Mandeville points where they would be able to enter the Warp. However, the jump point from which they had entered was now blocked by the Dark Angels, and so they had to present their backs to the enemy as they fled towards the antipodal point on the other side of the Davin system. Even as the majority of the remaining ships began to disappear around Davin, many ships still lay immobile. Some were obviously inoperable, vast slabs of hull sheering from their battered frames. Yet others seemed comparatively undamaged, holding in place with their shields up and ignored by the Dark Angels who maneuvered around them in pursuit of the main legion fleet.

Horus barked the last set of orders, and the Vengeful Spirit finally began to move. With encoded coordinates now transmitted, the fleet began to enter the Warp even as auspexes showed the incoming arrival of hundreds of ships, though their allegiance was unknown. Horus looked back, staring with fury and rage as a flotilla of heroes moved into position behind him. Led by Captains Marr and Moy, the so-called "Either" and "Or", a dozen or so ships formed a sacrificial blockade, giving their primarch the time he needed to escape his pursuers. Raising his fist in the symbolic gesture of Unity, Horus saluted his brave sons, refusing to look away as their ships were consumed in fiery explosions behind him.

Age of Darkness: The Heresy Revealed

The storms which assaulted the Sons of Horus fleet when they entered the Warp made their previous travel difficulties seem as minor breezes in comparison. The crescendo of bloodshed and betrayal had whipped the Immaterium around Davin into a frenzy, and the ships of the fleet were thrown to the winds. The Sons of Horus were trapped in the Warp, unable to control their direction or even return to realspace. The Gellar fields were perpetually on the brink of collapsing, and many did, their unfortunate inhabitants lost forever. When the storms finally abated, the Sons of Horus found themselves north of Davin, within the region of space known as the Golgothan Wastes. Originally known as the Golgothan Sector, this lawless region of space near the Maelstrom had been taken by the World Eaters in their first major campaign after reuniting with their primarch. Now it was barren and empty, nearly fifty worlds scoured of life by savage hordes of the Twelfth Legion, as dead as its conquerors now were. The only remaining known inhabited world was Sarum, a forge world of ill repute. When the fleet of the Warmaster moved into orbit, the Mechanicum there were quick to offer their support to the Warmaster, though not even Horus dared to go down upon the accursed planet.

After repairing the worst of the damage, Horus knew he needed to return to Terra to spread news of the betrayal of the First and Ninth Legions. As much as they desired to head straight there, the Prospero Sector lay between them and Terra, and traveling through the domain of the renegade Fifteenth Legion would surely slow them down. Thus they began to move to the northwest, towards the Chondax System, where perhaps they would find the long-missing Star Hunters or Death Guard. They passed through many systems of all descriptions, most of which had no idea there was a war going on. Some were utterly dead, while others were forgotten backwaters. Evidence of ork settlement was everywhere, though only as scorched remnants that made it clear that the Star Hunters had been there. Nearly a year passed before the Warmaster's fleet discovered forces from another legion, and by a stroke of luck, they were those of the Death Guard. The Horus of yesteryear would have been quick to hail his brother, but repeated treachery and assassination attempts had made him a harder man. Thus his fleet moved to surround the Death Guard, whose ships looked incredibly battered and rusted. Horus hailed the Endurance, and a Mortarion who was as scarred as his ships answered, causing a standoff between the two proud men. Horus began to let his guard down as his brother spoke of repeated Vth Legion assaults, who would attack at suicidal speeds to cripple vital systems such as the engines and Gellar Field generators, which rendered them unable to maintain Warp travel for very long. The standoff only worsened when auspexes revealed the presence of Space Wolves vessels among the Death Guard fleet. Suspicions were high on both sides, and the Warmaster demanded Mortarion submit to his authority. It seemed as though Horus was about to give the order to fire upon his brother's ships when he suddenly stiffened, his mind assaulted by a vision.

The blinking cogitators and flickering view screens of the Vengeful Spirit had vanished, leaving Horus standing within a ruined citadel, whose broken walls revealed a churning sea and a rocky coastline nearby. Looking at himself, Horus saw he was in the colors of the Luna Wolves once more. Beside him stood his brother Mortarion, though he was much cleaner than when Horus had seen him on the hololith.

"Witchery!" Mortarion hissed. Horus snorted at the unspoken accusation.

"You think I have done this? I don't even know where we are." Even as Mortarion moved to respond to Horus's denial, a new voice spoke.

"Peace, my sons. Time is short, and there is much to be done." Turning to the source of the voice, Horus saw his father standing before them, a golden warrior in his full regalia. Both he and Mortarion knelt before the Emperor, who impatiently gestured for them to rise. "You stand upon Damesek at the start of the Fulgurine Path upon the world of Molech."

Horus frowned. "Molech…why does that name sound so familiar?" Mortarion said nothing, clearly uncomfortable and out of his depth.

"You have been here before, though your memories were sealed away. You must regain that knowledge and stop the interlopers who come to claim power here."

"Interlopers? What are you talking about?"

"The day I have long prepared for has finally come. Half of my sons are lost to me, yet the First may be more dangerous than all the others combined. Molech must be protected. Go, my sons, find the Fulgurine Path, and all shall be revealed." His words complete, the vision began to fade away, and Horus found himself upon his flagship once more.

With no choice but to trust each other, the Sixteenth Legion began shuttling over the parts and personnel necessary to repair the vessels of the Death Guard and Space Wolves. Once completed, the fleet began to move further northwest in the direction of the Molech System. The loyalist armada arrived several months later, pushing through the storms to discover a planet wracked by war. Crusade records showed the world had been brought to compliance decades earlier by forces of the First, Third, Fifth, and Sixteenth Legions, yet it was none of these which were currently present on the planet. After the Emperor had withdrawn, Molech was fortified to a suspicious degree: nearly a hundred Imperial Army regiments and three titan legions now called the planet home. Yet the real architect of the fratricidal civil war they were picking up on auspex scans were two other legions. The Ninth and Thirteenth Legions had riven Molech into warring factions: it appeared the Ultramarines had the upper hand with the support of House Devine, the ruling Knightly House that controlled the Imperial Governorate. However, the Blood Angels had reaped a bloody slaughter, enticing the majority of Imperial Army regiments over to their mad cause.

In light of such massive forces opposed to them, Horus and Mortarion recognized a full-scale assault would only drain their legions. The strength of the Warmaster's fleets was more than enough to secure control of the void, so the two primarchs embarked upon their transports with only their elite bodyguard, landing in secret upon the island which the Emperor had imprinted upon their memories. As Horus paced around the ruins of the fortress that he had seen in his vision, memories from another time began returning, and Horus realized their goal could only be in one place: the Dawn Citadel, the fortress of the traitorous House Devine built from the wreckage of a ship said to have been used by the Emperor himself. Yet the Citadel was at the heart of Lupercalia, the planetary capitol, and was sure to be heavily guarded.

Overwhelming force would be needed, but that was no problem for the forces of the Warmaster. The drop pods began to rain down, and Lupercalia became a battlefield between the forces of the Warmaster and those of the Ultramarines. A fierce struggle ensued: the Ultramarines withdrew their forces towards defending their capital, the hedonist Knights of House Devine enraged beyond measure that any would enter their unholy city. By the time Horus and Mortarion had arrived at the outskirts of Lupercalia, the city was mostly theirs. Yet even as the Warmaster's forces recovered in this brief interlude in the fighting, a new threat arrived. The fleet in orbit announced they had been engaged by the forces of a new enemy. A grand fleet of the First Legion had arrived, the dread Dark Angels led by Lion El'Jonson himself, supported by forces from the Fifth Legion as well. The fleets of four legions began to clash in a colossal battle far surpassing the conflict above Davin two years before. Horus and Mortarion formed their forces into an unstoppable spearhead, pushing through the remaining Ultramarines as they pierced the defenses of the Dawn Citadel. However, the Citadel was as vast as the starship it was constructed from, and stretched far below ground, and each floor held new horrors and foes to vanquish.

Foul Astartes clad in the utter black of the Dark Angels made themselves known: searing plasma fired from Dreadwing Interemptors, lightning-fast Ravenwing swooping across the parapets, hulking Deathwing smashing into their Justaerin counterparts. It was clear the Dark Angels had utilized their infamous skill at teleport assault, and were buying time, slowing the Warmaster down from his objective in the lowest reaches. The further into the citadel they penetrated, the worse the horrors became: the metal and stone became fleshy and twisted, corridors looping back upon themselves, and gibbering monsters from the lightless depths threw themselves upon the loyalist spearhead. Yet slow the brothers was all they could do, for the enkindled fury of two primarchs is an inexorable thing to behold. Horus was unstoppable in combat, smashing through his brother's bastard sons while Mortarion was the creeping death, his mighty Silence reaping any that survived Horus's initial assault. Finally, they reached their objective, the hallways of the ship giving way to a natural cave, at the center of which stood a black gateway, etched with unholy symbols and partially obscured by the bloodied corpse of a woman, impaled upon its stone spikes.

Hideous whispers of betrayal and power wormed their way into Horus's head, promising him agonies beyond compare and glory beyond measure if he would just pass through the gateway. The Warmaster could tell his brother was similarly affected by the look of intense hatred upon Mortarion's face. The voices promised him the universe, yet he steeled himself, raising Worldbreaker that he might smash the gateway. Yet as he approached, a figure emerged from the Chaos Gate.

Lion El'Jonson emerged from between the stone arches. Yet this was not the brother Horus remembered. His brother's hair, once blonde, was now graying, and his immortal face was now etched with lines of age. Yet it was his eyes that bothered Horus the most. His brother turned his gaze upon Horus, and despite being a primarch, Horus felt unsure. This was the gaze of an apex predator. This was an unholy king, a figure of authority whose presence rivaled, no, surpassed Horus's own. Beside him, Mortarion seethed, his nature rendering him utterly opposed to everything the Lion now represented.

There was no doubt in Horus's mind anymore. Not Guilliman, not Magnus, not Sanguinius. This was the architect of the civil war and rebellions plaguing the galaxy. Here was the author of this…heresy.

Shaking off their doubts, Horus and Mortarion attacked as one. Two superhuman demigods in their prime, one the pinnacle of decisive offense, the other the unshakable defensive master. There are few foes in the galaxy that could withstand or outlast one primarch, let alone two. Yet the Lion was all this and more. The Lionsword, his power blade which once shone with a pale, pure light, now emanated a dark aura, a black beyond the deepest shadows that was rivaled only by his armor, and it moved with lightning fast speeds to block every blow thrown his way. Lion had long been renowned as the best at the blade among his brothers, and when he finally struck, his speed was incredible, so fast that even Horus's eyes could hardly keep up with it. Each strike inflicted a deep cut, its unholy aura slowing the other primarchs' superhuman biology from healing the cuts like it normally would.

Within a minute, Horus and Mortarion were both on their knees, Worldbreaker and Silence buried in nearby walls from precise disarming strikes that swept them from their owner's hands. The Lion stood above them, blade in hand, when he reached down, and picked up several objects from the ground. Horus looked down at his own chest, realizing the object the Lion held was the Eye that had once sat upon his breastplate, though he was unable to see the other object. The Master of the Dark Angels stepped back, walking back towards the now-dormant gateway to retrieve his winged helm from where it was laying. Their brother had not said one word since he had emerged from the gateway, and placing his helmet on, regarded them silently. A bright flash filled the room, overpowering the meager torchlight, and when it faded, the Lion was gone.

Horus and Mortarion returned to the surface, their wounds healing as they walked. When they reached the upper levels, they learned Molech had been secured, the traitor fleet having retreated after the Lion had returned. Horus was unsure what exactly that gateway was, but was certain it was pure evil, a wound upon the world. Whatever the Lion had done within that gateway, it had made him incredibly powerful, enough to defeat two primarchs and more. Returning to his ship, Horus ordered Molech be scoured, and he watched with bitter satisfaction as the world died below him, the traitorous Imperial Army and Blood Angels annihilated as the deadly Life-Eater virus did its gruesome work.

Legacies of Betrayal: Bastion Omega

The forces of the Warmaster began their journey back to Terra. Horus spent most of the journey in meditation, hoping for some sort of sign from the Emperor, though none were forthcoming. He felt utterly out of his depth for the first time in his life, unsure of who he could trust and what he should do. The storms were just as bad as they had been, and so the fleet could only make short jumps, hopping from system to system to minimize the time spent in the Immaterium. Many of these systems held scattered Imperial Army forces, all holding their positions waiting for orders that might never have come. Horus and Mortarion began to deposit their forces on these planets, creating a line of defense on the planets that lay on the route to Terra. By the time the forces of the Warmaster reached the Solar System, they had shrunk down to half their original size. Many worlds now served as a secure rearguard, including Fenris, where the remnants of the Space Wolves had departed to recover and resupply on their homeworld. When they finally arrived, they received a cold welcome, halted by the Salamanders at the system's edge. Horus took little satisfaction in his brother's alertness, and was finally allowed past the Elysian Gates due to the direct intervention of Vulkan himself. As his fleet transited the system, Horus was intrigued to see the presence of Iron Hands fleets surrounding Mars. Horus and Mortarion embarked upon their personal transports, and were taken down to the Imperial Palace while their sons remained in orbit, subject to searches by teams of wary Salamanders.

Once within the Palace, the two primarchs met with Vulkan and Ferrus Manus, and swiftly brought each other up to speed on what had transpired in the past few years. Vulkan and Ferrus both seemed much as Horus remembered them, though they had clearly undergone trials of their own. Horus did not wish to remain on Terra, for waiting for the enemy to arrive was not his nature. The four brothers took time to plan their next moves, and Horus returned to his ships, ready to put their plan into motion. Before leaving Terra, Horus ordered the Remembrancer Order dissolved, for none should bear witness to such a war of father against son, of brother against brother.

However, bringing justice would require the tools of war. Horus met with his old friend Kelbor-Hal, the Fabricator-General of Mars, who agreed to lend his expertise and resources to repairing the fleet of the Sixteenth Legion in exchange for their aid in reclaiming rebel forge worlds. Mars itself was lost, the site of ongoing battles between the Iron Hands and Dark Mechanicum rebels, but enough forges had been retaken to reopen the supply routes once more. After several weeks of rearming, the Sons of Horus set out to begin the first phase of the operation. They left behind what remained of the Legion Auxilia, as well as Mortarion and his sons, for they had their own role to play. The Sons of Horus were on the move once more, split into dozens of fleets that prowled the stars like the wolves they had once named themselves. Their goals were simple: annihilate the enemy and any who gave them aid.

The first to feel their wrath was the Xana System. Xana II was an ancient forge world in Segmentum Obscurus with a proud history, having bent the knee to Holy Mars only through force. With the Forge World Principal fallen silent in the wake of a traitor assault, Xana had declared itself independent once more, and the last transmissions had indicated they were throwing their lot in with the rebels. This could not stand, for Xana II was one of the few worlds capable of creating the mighty Ordinatus siege engines, powerful constructs whose firepower rivaled that of titans. Leading the bulk of the Sons of Horus detachment was three of the four Mournival, commanded by Abaddon while Horus himself moved onto other worlds. When the forces of Abaddon entered the orbit of Xana II itself, its defenses sprang to life when they sensed the unwelcome interlopers. What looked like spikes upon the ring of iron which girded the forge world revealed themselves to be hideous constructs, mechanical kraken the size of strike cruisers that latched onto legionary vessels. Massive beaks of adamantium pierced the loyalist hulls, venting their unlucky inhabitants into the cold embrace of the void as other ships turned their guns upon the monsters. Despite such ferocity, the Sons of Horus were fiercer still, and soon gained control of the atmosphere. Xana would be no good a smoldering wreck, and so it would need to be taken from the ground.

Hundreds of drop pods filled the skies of Xana, hurtling at incredible speeds in order to avoid the clouds of flak that would have torn any landing craft to shreds. Abaddon had received an encoded set of coordinates from hidden cells of loyalists when they entered the system, and so the Sixteenth Legion moved to secure vital points across the Forge World. The forges of Xana had changed: where bright orange flames once lit the skies, now sickly green flumes choked the atmosphere; hideous semi-organic factories spewed forth maddened skitarii constructs who canted mad code that bruised the machine spirits of the loyalists. Their main goal was the Prison-Forge, the largest factory district upon Xana which held the mighty Ordinatus Engines. Speed was of the essence: if they were brought to bear, nothing short of a titan legion would be able to halt their rampage and Xana would be lost. Even as Abaddon's forces closed in on their goal, desperate cries from the ships in orbit started rolling in. Emerging from the shadows of Xana's moon was a single ship, the Dark Sovereign, a vessel from Old Night that belonged to the Dark Angels. Ancient guns began to fire, and the Sons of Horus vessels began to die one by one even as their forces did on the ground. Yet despite this Abaddon could not return to his ship, for retreat would see them all dead.

Desperation lent the Sons of Horus speed, and through heavy casualties they managed to take the Prison-Forge before its mighty Engines could be unleashed. Within its twisted halls, Abaddon found the source of the transmissions: the Vodian Magister, Anacharis Scoria. The genius Magos had once ruled Xana with his council in deference to Mars, though fate had not been kind to him. Stripped of his augmetics and interfaces, Scoria had been imprisoned and tortured for his command codes that would allow the rebel council to take full control of the forges of Xana. Having slaughtered the guards, Abaddon returned Scoria's missing implants, and the Magister interfaced with the Prison-Forge. His codes swept across Xana, overriding the scrap-code infested subroutines with inexorable clarity. The guns of Xana fell silent, and then turned as one upon the Dark Sovereign. Even the ancient shields of that cruiser could not withstand firepower of that magnitude, and the Dark Angels vessel was reduced to burning wreckage.

While Abaddon's forces took the Xana System, Horus sent the most elite of his forces under Hastur Sejanus far to the northeast on a special mission to secure a prize of utmost importance: the Rangda System. The center of a once-mighty xenos empire, the Rangda had been broken primarily by the might of the Dark Angels, who had been forced to employ weapons of unimaginable potency to counter the monsters from the dark. However, the treachery of the Lion worried Horus, for any surviving xenos relics would prove an unparalleled danger in the wrong hands. Thus Sejanus moved with a small force capable of piercing through the storms to reach Rangda space quickly. Sejanus's ship, the heavy cruiser Conqueror's Pride, entered the Advex-Mors system nearly a year after departing. The Astronomican's light was faint out here even before the storms, and thus it had been incredibly difficult to locate the system. The system had once held a chapter of Dark Angels known as the Order of the Broken Claws, who had been assigned to keep eternal watch over what was believed to be the homeworld of the Rangda. Yet their watch fortress which hung above the sole world in the system now lay empty, its databanks as scoured as the planet below. Sejanus ordered a final sensor sweep of the system before retreating from the silent world, for some things were better left alone.

While his Sons did their duty far from Terra, Horus led a rapid reaction force, moving from world to world in response to calls for aid. Across a chevron front stretching from Cypra Mundi to Trisolian to Phaeton, the defensive network known as Bastion Omega slowed the traitor advance. Horus's forces defended the southern flank, consisting of the worlds south of Trisolian, while the Space Wolves and the Death Guard watched the northern. The main threat to this flank came from the Imperial Fists, though by this time, many had begun calling them the Crimson Fists. The forces of the Seventh Legion struck from many angles, and were based out of the Inwit Star Cluster, Dorn's personal fief. The Warmaster refused to give up worlds without a fight, forcing the Fists to siege down world after world. Horus grew more bitter with every world under his protection that he was forced to surrender as his lines were pushed ever back.

Horus and his Sons fought the traitors for control of Bastion Omega for three long years. At their side were forces from many legions, though none stayed long. Many heroes fought and died in these dark days: Falkus Kibre, Grael Noctua, Garviel Loken, and hundreds more besides. The war took them and many others, and by 020.M31, the legion was a shell of its former self, forced to pull back to Terra from Trisolian after extended conflicts against the forces of the Emperor's Children. The Third Legion had changed much since the Sons of Horus had last faced them. Great clouds of ash and soot suffused every battlefield in which they fought, sapping the will of the Imperial Army who faced them by their mere presence. Fulgrim's sons took far too much punishment, dragging out every engagement far beyond its natural conclusion. Horus sought out his brother many times, but Fulgrim never took the field against him, allowing his sons to slowly whittle down the Imperial defenders. The legendary charisma of the Warmaster had seemingly faded, and the humors of the Mournival were thrown out of balance after the death of Captain Torgaddon at the hands of Lord Commander Eidolon of the Emperor's Children. Even victories against the Third Legion were hollow: though the enemy had fallen back, they left filth and disease in their wake, rendering planets unlivable.

The Bastion Omega finally collapsed after the catastrophic defeats on the other fronts at Verzagen and Beta-Garmon. The Sixteenth Legion had not been a part of these defeats, holding their flank against the relentless probing of traitor raids. Yet despite the fact they had not lost, the other defeats meant they were dangerously exposed in a salient that could turn into an encirclement at any time. Thus the legion was forced to fall back, abandoning their positions in favor of reinforcing the Solar System. The Warmaster now presided over a much smaller legion: barely fifty thousand, just over a third of what it once was at its height. Recruitment from Cthonia had slowed to a trickle before it was finally cut off due to the traitor blockade of the Solar System, and only a skeleton force remained as garrison. The bulk of the legion gathered around Terra, resupplying in preparation for the traitor assault.

The Solar War and Siege of Terra

On the first day of the first month of 020.M31, the traitors arrived. The legions of Hell forced their way into the Khthonic and Elysian Gates, clashing with the vastly outnumbered Imperial forces assigned to defend them. Horus himself was not at either of these battlefields, for his fleet had been assigned to maintain the defenses of Jupiter. The Sons of Horus fleet waited anxiously, watching light from the battles arrive hours later as it reached where his forces held their positions. Though he burned to join the battle, Horus knew Vulkan's plan was a sound one, and so he maintained his position, making last minute adjustments to those under his command in the Third Sphere Defense Forces. The Warmaster waited for the traitors to arrive like he knew they must, and they did not disappoint, arriving in pursuit several days later shortly after the last of the First and Second Sphere forces had retreated past his lines.

The guns of the Sixteenth Legion lit up as the first of the Iron Warriors vessels came into range. The loyalist forces were spread thinly across the moons of Jupiter, as well as the Jovian Shipyards and the maze-like debris fields known as the Caul. Thousands of kilometers above, the Polar Shoal city-stations began to lob plasma mortars into the traitor lines that swarmed towards them. Supported by guns firing from every angle, the Sons of Horus made their counterparts pay a heavy toll as they fought their way into position to begin landing their armies on every station and moon. Yet the sons of Perturabo found no respite there, as the Warmaster's armored battalions rolled out to annihilate the landing craft and drop pods wherever they made landfall. Horus himself soon took the field, crashing through the Fourth Legion's hastily-erected siege camps in a grand mechanized spearhead.

Yet for every traitor that fell to Worldbreaker or the guns of his allies, it proved to be hopeless in the end. During the three years of Bastion Omega, Horus had used his authority as Warmaster to relieve his legion of the duties of the Edict of Nikaea, and his Librarius had come back into full force, with the Chief Librarian kept at his primarch's side to protect him from the foul sorceries of the enemy. Xavyer Jubal, recalled from the ranks of his brothers to serve in this role once more, acted as the voice of the legion, relaying messages to and from the Warmaster from his psychic brethren spread throughout the ranks of the legion. With his aid, the Sons of Horus were able to efficiently communicate despite the chaos of the battlefield. However, this communication network began to break down as the psychic brotherhood engaged rival sorcerers of the Thousand Sons, who began a catastrophic ritual taking place within Jupiter itself. Even as the remnants of yet another Iron Warriors battalion fell back in disgrace, the Sons of Horus watched as the Great Red Spot rotated into view, a lidless, fiery eye of horror and madness that assaulted their minds with terrible visions and whispers. From its depths spewed ships beyond count, and at its center were tens of thousands of Astartes vessels, the rest of the traitor legions which had not yet been seen. The Sixteenth Legion fell back in a fighting retreat, having known they could not hold the world forever, though they were not prepared for such a force of nightmares to emerge. As their ships fell back, the Jovian Shipyards detonated as explosive charges went off, destroying any traitor vessels caught in the blast radius.

Several weeks of time had been gained, though at high cost. Nearly forty percent of the legion perished defending the Third Sphere, and now only thirty thousand Astartes remained to guard the walls. However, these were the Warmaster's legion, the best of the best, trained through centuries of warfare, and they brought their experience to bear upon the battlefields of Luna. What remained of their once-mighty fleet fought one final time above the dark side of the Moon, clashing with the combined traitor armada which had now linked with their debased kin already present. The greatest fleet battle in recorded history took place that day, yet from the beginning, it was obvious who the victor would be. After days of continuous fighting, what remained of the loyalist fleets broke away, falling back until reinforcements could arrive. While the fleets battled above, the Sons of Horus fought below, having returned to their roots as they defended Luna on every level. The traitors were forced to take every position, starting with the mighty fortress Ring that girded the Moon. Below it lay a vast series of canyons known as the Circuit, its walls dotted with fortresses. Once these bastions had belonged to the Silent Sisterhood, though its inhabitants had long since left, and now their halls were filled with the forces of the Warmaster. Deep under Luna lay the gene-labs of the Selenar, where the first batch of mass-produced Astartes had sprung forth, and it was here the heaviest defenses lay, the elite 5th Company led by "Little Horus" Aximand.

Aximand had known this assignment was suicide, and yet here he was all the same. His aspect of the Mournival had always been that of the waning half-moon, of the slow death of Autumn, and he had brought death to the many foes sent against him. Hundreds of traitors in the stone-gray of the Crimson Fists lay strewn around him, many cast down by him personally and his blade Mourn-it-All, which now lay in pieces around him, shattered by the last strike from Sigismund's black blade.

Aximand was kneeling now, forced down by the relentless attacks of his black-armored foe. He lived a good life, he supposed, and would now die an honorable death. He looked up at the face of his killer, preparing to make one last biting remark, only to see a blur, for the blade had already leapt into motion.

Aximand's head rolled on the floor before being kicked aside by Sigismund's armored boot. His lifeless eyes watched as the Grandmaster entered the doorway to what had once been the Selenar Gene-Cults laboratory complex. Within lay the genetic data and resources to make an entire legion.

Horus himself had remained in the Palace after retreating from Jupiter, and emerged alongside his brother primarchs to stand on the Walls as the first shots from orbit began to rain down. Except for the detachment under Aximand and the small garrison upon Cthonia, the entirety of the Sixteenth stood with him, spread across hundreds of miles of walls, and there they remained, ready to act as a spearhead should the traitors draw too close. Tired from years of deceit, hard choices, and retreating, Horus was gladdened when Vulkan told him it was time to join the battle, and the Primarch of the Sixteenth showed why he had been named Warmaster. With his two favored sons Abaddon and Sejanus by his side, Horus struck the traitors time and time again, keeping them off-balance with masterful strikes.

All the traitor legions present felt the wrath of the Warmaster. For well over a month, the Warmaster's forces fought and died in stupendous numbers against those who had turned their backs on the Emperor. Across Terra, the raiding forces of the Ultramarines, Thousand Sons, and Emperor's Children clashed with rapid reaction forces of the Sons of Horus, who had joined the Salamanders in defense of the hive cities. The siege-camps of Dorn and Perturabo buckled and splintered, struck hard by spearheads of assault troops led by Horus that fell back after damaging their mighty engines. Even the rapidly-growing fortress of the Dark Angels came under assault, though they were swiftly pushed back with heavy casualties. The legionaries slept only a few hours per day for weeks on end, even the wounded taking their turns on the wall, and their primarch shared in all their sufferings. Shortly after this last and most audacious raid, Vulkan ordered Horus up to the Eternity Wall to repel the traitors who had landed there. The Death Guard had just retaken the Raven's Gate Spaceport, and so they sought to seize the Eternity Wall Spaceport in order to keep landing troops. The Sons of Horus along with the few Legion Auxilia left spilled onto the walls, and found the source of the threat: the Blood Angels and their berserk primarch, Sanguinius.

Debris continued to rain from the sky, falling past the weakly-flickering Aegis that struggled to remain lit above the Walls. Something had happened in orbit to drive the traitors into a frenzied push, but it didn't matter. Horus recognized these thoughts were only distractions, his mind's attempts to stay calm despite the horror before him. He glanced at his armor's internal chronometer: the 29th of Quintus; had they really been fighting for that long? Several hundred meters away, the daemon that was once Sanguinius rampaged through the loyalist lines, utterly unstoppable. The primarch of the Blood Angels was his brother no more: in his place was a towering behemoth bedecked in remnants of golden armor, taloned hands clutching the Blade Encarmine which was currently buried in the throat of one of his Sons. Boiling blood poured from Sanguinius's back, where the stumps of his once-beautiful wings had once been, while molten imprints in the ground behind him revealed the palpable heat radiating from the beast.

Horus began running now, headed straight for the daemon which took notice of him and charged in response. The monster's presence stirred his sons into new depths of rage, and hundreds of Astartes from both legions battled all around as the two demigods began to clash. Horus refused to call the daemon by its name, fighting in utter silence alongside Abaddon and Sejanus. The three were in perfect synchronization, Horus holding the daemon's attention while his sons made attacks of opportunity from the side when they could. The daemon soon began to bleed from more than just his stumps, pierced dozens of times.

Moving with as much speed as he could muster, Horus moved in for the final blow, only to be smashed aside by the daemon, the right side of his skull caved in from a blow even he'd been unable to avoid. The monster had anticipated his movement, dodging Worldbreaker even as he used his foul powers to manifest the Spear of Telesto from nowhere. The once-golden spear, now a foul brass soaked in viscera, reversed directions, plunging its head into the chest of Ezekyle, killing him instantly.

The rage which Horus had pushed down threatened to boil over in that moment. In that brief time, Horus wanted nothing more than to scream and fly at Sanguinius, to tear him to pieces for murdering his sons and betraying their father. Yet to do so would only play into the daemon's plan. No. Horus would not give in to rage like this monster.

The golden light of the Emperor began to shine around him as he walked towards Sanguinius, who was distracted in his fight against brave Sejanus, who was utterly outmatched yet fought all the same. Horus grabbed Sanguinius from behind, holding him tight even as scalding blood burned through his armor. The Emperor's Favored Son lifted the Angel above his head, and cast him from the heights of the Palace, sending him screaming as he fell from sight to the fires of battles below.

Banished by his utter defeat and fall from such a great height, Sanguinius was cast back to the Warp from whence he came. The pressure on the defenders lessened, both spiritually and physically. The Blood Angels were utterly lost with the fall of their father: it seemed as though it had been his presence which drove them to such fury, and without him they lost their sense of purpose. The all-consuming rage which had threatened to overwhelm the defenders faded as the last of the Ninth Legion fled the walls of the Palace, leaving them exhausted and spent. Despite this, the Sons of Horus were in no position to follow up on their victory. Their primarch was unconscious and badly wounded, his body covered in burns from Sanguinius's corrupted blood. Unable to pursue the retreating traitors, the Warmaster's sons instead fell back towards the Inner Palace to recuperate, and remained on the defensive for the rest of the Siege.

Though unknown to the Sons of Horus, their victory over the Blood Angels had occurred in tandem with the Iron Hands' defeat of the Emperor's Children at the Saturnine Wall, and it was these two hard-won victories that turned the traitors' attention away from the battle in orbit. Even as they were committing their reserves into the conflict, the forces of Lorgar struck from above. Within days, the traitors were falling back across Terra, and word soon came from Lorgar that the Lion had been defeated. Horus himself awoke several days later. His burns were healed, yet his eye had not; he would bear that injury for the rest of his life. He was devastated to learn that Konrad had been killed and the Emperor had fallen, and his grief was only deepened when he learned his brothers had each received a vision while Horus alone had not. Burying his anger, Horus gathered his forces, leaving Terra with his legion after disbanding the Legion Auxilia and sending its members back to their own devastated legions. The forces of the Warmaster departed after the funeral of Konrad Curze and returned to Cthonia, which had not come under attack despite its relative proximity to the Solar System.

There Horus remained for years, brooding as he rebuilt his legion. The final surviving member of the Mournival, Sejanus, took charge of the legion, overseeing its operations and rebuilding it alongside the other legion commanders. As Horus remained sequestered, his ill temper grew at a rate matched only by his grief. Already, with his father's ascension to the Golden Throne, the scheming bureaucrats upon the Council of Terra were renewing their claims to power and prestige that none of them had earned. While he and his brothers and their sons fought for years to defend the Emperor's realm, they had hid, safe behind Vulkan's walls and criticizing the Warmaster for not being more successful. However, Horus was no berserker, and he knew to take his frustration out on his allies would only be detrimental. Thus he resolved to vent his fury upon those who truly deserved it, the unworthy traitors who had turned their backs upon the Emperor, upon his leadership as Warmaster.

The Scouring: A Vengeful Spirit

The forces of the Warmaster returned to Terra, where in his absence, Lorgar and Malcador had ruled. With their support, Horus announced the beginning of a new era of the Imperium, a grand campaign worthy of the Great Crusade that would wipe the traitors from existence. Vast numbers of Terra's population watched the public view screens adoringly as the first of the Warmaster's fleet took to the stars, to drive out the traitors from their fortresses and remove their taint from the realms of Mankind. Thus began the Scouring, the first phase of the Age of Rebirth, and the start of the Age of the Imperium.

The Sons of Horus made up the bulk of this initial fleet. Even after the traitors had fled from Terra, the wars had not ended. For several years now, vengeance fleets of Iron Hands and Word Bearers had struggled in small skirmishes against entrenched traitor worlds. But now the speartip of the Sons of Horus had come to break their defenses, to send them back to the hell they now served. Horus showed yet again why he had been named Warmaster, utilizing his strategic genius to direct the myriad armies and fleets under his command. Many forces thought lost turned up at Terra, though some came to Horus himself for direction, where he would receive them and decide where they could be of use. One such example of this was the arrival of Arkhas Fal and his Ashen Claws. Horus had long favored Fal, and had been confused when Corax had sent him away. With Corax dead and their numbers depleted, surely the Raven Guard would appreciate the reinforcements? Fal swore his loyalty to Horus, and was given a commission to return to Deliverance and bring his legion to aid in the Scouring.

Horus and his Sons fought at the forefront of the Scouring for over ninety years, bringing much needed hope to the oppressed and despondent peoples of his father's Imperium. They pushed the traitors back on every side, venting their fury upon those they once counted as allies and sending their scattered remnants fleeing into Warp storms. Alongside Ferrus and Mortarion and their legions, the forces of the Warmaster crushed the foe wherever they could be found, and none could stand before them. Their task was aided by their foes turning upon themselves: many worlds were found shattered and broken, their Legion garrisons having left or turned upon their rivals. In between campaigns, Horus would travel back to Terra and consult with his brothers on the shape the Imperium was taking. The need to prevent another Heresy was paramount, and thus Horus proposed the Edicts Martial.

Edicts Martial

Despite the preeminent role the Legiones Astartes played in the Heresy, the Heresy was truly a civil war. Because of the sheer size of the Imperium, most worlds never even saw space marines, loyal or traitor, during the conflict, instead being ravaged by their own internal civil wars. The Imperial Army, long looked down upon as inferior to Astartes, had undergone its own fratricidal conflict as billions of mortal soldiers fought each other in the name of the Emperor, the Lion, settling old scores, or even just independence.

To prevent such conflict from occurring again, the Imperial Army was split into the Astra Militarum and the Imperial Navy. Thus any rebellion would be either unable to move between worlds or unable to hold them. Both branches were subject to the Departmento Munitorum, and each received representative status among the High Lords of Terra, ensuring vital manpower would not be wasted. In addition, these forces and their chains of command were to be kept separate from the Legiones Astartes. Cooperation was allowed, but neither were able to directly command each other.

With the newly formed Astra Militarum, or Imperial Guard as it came to be known, the Astartes Legions were now able to turn over control of their many worlds. Freed from garrison duties, the Astartes became a more elite force, taking the fight to the enemy and finishing up the Scouring. Even though Horus had sponsored the creation of the Imperial Guard, he often found himself troubled by them. After word of the Emperor's entombment upon the Golden Throne had spread, many had come to regard him as divine, a sentiment Horus strongly disagreed with. Despite repeated persecutions and crackdowns, it seemed like the new faith, so reminiscent of Lorgar's former worship, was only growing.

However, such concerns would have to wait until after the current campaign. One of Alpharius's many spies had indicated the possible whereabouts of a traitor primarch, and Horus made with full speed for the location, his brothers indicating they were en route but days behind. Horus had long pursued his traitor brothers, seeking to avenge their father's death in person, yet so far they had avoided his wrath. There was no time to wait for reinforcements, thus only the Sons of Horus, along with a small Space Wolf detachment, were present to accompany the Warmaster to the system of Sebastus IV.

Hounds of Abaddon

In the wake of Horus's return to Terra after the Treachery on Davin, one of the many forces accompanying him were several companies of the Sixth Legion led by Geigor Fellhand. Most of the Space Wolves quickly departed, returning to Fenris to lick their wounds, yet some remained. Led by Halvdan Bale-Eye, this demi-company hailing from the ranks of the 13th Great Company was assigned to fight alongside First Captain Abaddon and his Justaerin Terminator elite. Both Halvdan and Abaddon grew close to each other through their many campaigns, and even after Abaddon's death at the hands of the Daemon Primarch Sanguinius, the Wolves remained with the Warmaster, naming themselves the Hounds of Abaddon in his memory. Thus the Hounds were at the Warmaster's side even a century after the Siege of Terra, sworn to fight under his banners until death claimed them.

What greeted the Sons of Horus was a scene of utter devastation rivaling the Siege of Terra itself. Thousands of ships from the Iron Warriors and Crimson Fists hung broken and shattered in the skies above Sebastus IV. It was clear a titanic struggle had taken place here, a struggle won by the IV Legion, whose carrion slaves even now picked over the bones of entire fleets. Upon Sebastus IV itself lay a massive fortress, a dark mirror of the Imperial Palace that echoed the brutalism of its creator. A short band vox transmission issued forth from the vast structure, an unencoded series of taunts from the master of the Eternal Fortress, the primarch Perturabo. The Primarch of the Iron Warriors boasted of his victory over his brother Rogal and the Fists, and dared the Warmaster to assault his creation, claiming nothing but perpetual pain awaited him within the daemonic fortress. Horus's fury was stoked anew at his brother's boastful claim. Never one to shy away from a challenge, Horus swore to dig Perturabo out of this iron cage, and began his assault.

After blasting a path through the wreckage in orbit, the Sons of Horus landed in force upon Sebastus IV. Sieging the fortress was unnecessary, for while the Crimson Fists may have been defeated, they had left grievous wounds upon the structure that Horus exploited to the fullest. Yet vast numbers of Iron Warriors still remained, and the battle became bogged down. The Eternal Fortress was truly massive, for the Iron Warriors had clearly been working on this for far longer than anyone had realized, and there were any number of locations Perturabo could be hiding. Even the keen senses of the Hounds of Abaddon could not locate him, only rooms and chambers where he may have once been.

Hours turned into days, and days into weeks, as one fortress wing after another fell. Horus's sons died in numbers equalled only by their foe as they pushed into the heart of the fortress. Horus became separated from the bulk of his sons, for the fortress was vast indeed, with death lurking in every chamber. Perhaps had more of the Mournival still lived, they would have accompanied him, or advised caution instead of headlong rage. Such was not the case though, and Horus plunged deeper into the fortress, certain Perturabo would be located within the deepest recesses just as the bridge of Iron Warrior vessels lay at the heart of their ships. As Horus entered the center chamber, he came under an assault far exceeding anything that had come before. Separated from all but his elite Justaerin bodyguards, Horus was attacked by wave after wave of machines, unshackled by the laws and restrictions of the Adeptus Mechanicus. Perturabo had long been known for his skill with machines and technology, but such a blasphemous union of Abominable Intelligence and daemon was unparalleled. One by one, his bodyguards fell, until it was just Horus alone.

Even as he crushed the final machine beneath Worldbreaker, waves of Iron Warriors emerged from concealed doors in the walls. They had no hope of killing the Warmaster, yet still they came. Battered after hours of fighting, Horus was nearing his limit when Perturabo finally emerged. The Lord of Iron had never boasted of his combat prowess like some of his brothers, yet whether it was skill or Horus's exhaustion, he proved a formidable foe indeed. His mighty Logos armor absorbed all the blows Horus threw at it, while his mighty warhammer proved the equal of Worldbreaker.

Yet for all his disadvantages, Horus showed once more why he had been named Warmaster. Despite his weariness, Horus cast down his brother, breaking his armor and weaponry through a series of titanic blows. As he stood above his fallen brother, Worldbreaker raised for the final blow, Perturabo's body began hissing, the blood leaking from his many wounds shifting from red to black. Mocking laughter rang out from hidden speakers as the Logos opened, revealing not the Iron Within, but rather a screen displaying a countdown attached to a tactical nuclear device. The coward Perturabo had never been there at all, rather having sent one of his daemonic machines in his place. Dropping his maul to the ground, Horus made the Sign of the Aquila even as the device went off beside him. Thus died Horus Lupercal, the First-Found Son and Warmaster of the Imperium.

The resulting destruction from the explosion ripped the heart out of the Eternal Fortress, and the remaining Iron Warriors fell back quickly afterwards, leaving the distraught Sons of Horus to their grief and the empty fortress. Within a day, the Death Guard and Iron Hands arrived, but they were too late to aid in the battle. No trace of the Warmaster was ever found save for Worldbreaker, the mighty maul given to Horus by his father so long ago, and a single gauntlet bearing the Primarch's mighty talons. It is said that the entire legion howled with grief that day, and none more so than Sejanus, who swore he would have given his life to change fate.

The Brotherhood of the Wolf

The resulting blast from the device that claimed the life of the Warmaster left many of the closest survivors with scorched-black armor. Swearing vengeance for their fallen primarch, many of the Sixteenth Legion fell to rage in those days, calling themselves the Luperci in honor of their father and swearing to never repaint their armor. Sejanus himself was the first of these, and after naming four new successors, he resigned his position on the Mournival to join the Luperci in search of glorious death.

The death of their father has resounded down the centuries, and even millennia later, the Luperci still exist. They are clad in mighty terminator armor, ritually scorched upon entry to the brotherhood, and are sworn to oppose and uproot Chaos wherever it may be found. The early rage has given way to a simmering hatred, but only those who have mastery over their humors, such as Sejanus once did, are allowed to swear the oaths of entry. They alone recognize that Horus's death was caused by his own passions, and refuse to go down the same path, suppressing their emotions and fighting in calm silence. Luperci are utterly resolved to destroy Chaos wherever it may be found, and are particularly vengeful against Traitor Astartes.

The shattered Sixteenth Legion fell back to Cthonia once more to recover from their grievous casualties. Command of the Scouring passed to Lorgar, who used his authority to pass an Edict of Toleration less than three years later. Sejanus considered this a betrayal of the Imperial Truth that the Warmaster had sworn to uphold, and a rift developed between the two legions that was only resolved after the death of Lorgar two years later at the hands of Guilliman. Though they are no longer at odds, tensions between the two legions continue to persist. The Sons of Horus gradually recovered, growing in size once more, and by the turn of the millennium, they were counted as one of the larger legions. Thus they were at the forefront of the War of the Beast, clashing with the greenskin menace just as their forebears did a thousand years before at Ullanor. Since that time, the Sons of Horus have fought on uncountable battlefields and against many foes. No matter the threat and no matter the odds, they have risen to the challenge, and no other legion has yet to match their many victories.

Homeworld, Recruitment, and Gene-seed

Even more than their legendary ferocity, the Sons of Horus can attribute their many victories to their relentless discipline. The legion strives for balance and discipline in all things, and it is the first lesson any recruit learns. Their determination has been well-rewarded, for they maintain one of the largest legions in the Imperium, nearly one hundred and twenty thousand Astartes strong. Only the Night Lords rival them in size, and the two legions maintain a friendly rivalry because of it. Unlike most legions, the Sons of Horus do not patrol the fringes, instead patrolling the vast central part of the galaxy. Cthonia itself lies incredibly close to Terra, and as such, has remained undisturbed for millennia, protected by the ceaseless vigil of Battlefleet Solar. From the edges of Segmentum Solar, where the Salamanders hold sway, to the borders of the Eparchy of New Monarchia where the Word Bearers patrol; betwixt the bastion-worlds of the Iron Hands and the realms of the Raven Guard; within this vast quadrilateral spanning most of the galaxy do the Sons of Horus patrol. Many chapters of the Sons of Horus have established permanent garrisons on worlds throughout the area so as to better guard these undefended regions. These chapters maintain permanent garrisons upon dozens of worlds, generally near minor Warp storms or known Ork migration routes. It is a tireless and Herculean task, but one that is fitting for the best and brightest of all the legions, and the Sixteenth have proved their mettle as they maintain the realms of men against all foes.

Like most Astartes, the legion most often fights alone, or with one of their cousin legions, but their sheer size means they have helped the forces of the Imperium on many occasions. One such crusade took place between 392 and 399 M41. Known as the Macharian Crusade, this colossal venture gained the Imperium the region now known as the Halo Zone, an expanse right on the edge of Segmentum Pacificus. Forged by the efforts of Lord Solar Macharius, one of the most brilliant Warmasters since Horus himself, the Macharian Crusade spearheaded beyond the limits of known space and brought over a thousand worlds into compliance. However, Macharius died incredibly young in mysterious circumstances, and after his death, his generals turned upon the Imperium and attempted to carve up his conquests for themselves. Led by Warmaster Imset himself, the Sons of Horus intervened and restored order to the Halo Zone. Even now, centuries later, the Sixteenth Legion still patrols the regions taken by the Crusade, on guard against both treachery, as well as threats from beyond.

Like most legions, the Sons of Horus recruit from but one world, Cthonia. Their homeworld is much as it was during the days of the Great Crusade: feral, savage, and on the verge of ruin. The legion has tried many times to repair the infrastructure, but it seems as though the world itself rejects their attempts, hive-quakes undoing any progress made within a matter of years. The people of Cthonia are as savage as their world, divided into innumerable tribes and gangs who squabble over the precious resources periodically dropped upon the pyramidal hives that dot the surface. Below these hives lies a vast underworld. Tunnels and warrens beyond counting snake below the surface, and it is speculated Cthonia possesses a much greater population than is known. These catacombs are believed to have been created by the miners which once inhabited Cthonia, though the planet has long since been stripped of any valuable minerals. To call them tunnels is an understatement though, for these chambers soar hundreds of meters in diameter, housing both the living and the dead, and it is within the largest of these that the Fortress-Monastery of Cheops sits. The Monastery is built from the wreckage of a hive, and soars kilometers above the other hives nearby, rivaled only by the Fang of Fenris in size. Its insides are incredibly convoluted, and only true sons of Cthonia are able to find their way around it.

Aspirants for the Sixteenth Legion are taken from the many gangs that call Cthonia home. Monitoring these gangs for both potential recruits and signs of corruption is truly a monumental task. Any surveillance technology is stolen with remarkable speed, stripped for salvage and sold as fast as they are put up, and thus the Astartes themselves must patrol the many tunnels. Their armored vehicles are the only faction able to pass freely among the fiercely territorial gangs, and many children flock to them as they pass, hoping to impress the legionaries with stories of valor that they might join their ranks. However, only the truly brave and ferocious are worthy to be implanted with the Warmaster's gene-seed, and so gang fights continue even while the patrols pass through their midst, the tribes hoping to attract the notice of their betters.

Each chapter of the legion is unique, its culture akin to these gangs of Cthonia. The gang affiliation of individual aspirants is irrelevant, and its members set aside their former ties to swear new oaths to their company and chapter. Each chapter is different in size, depending on casualty rates and number of companies, and the various companies compete amongst each other just as the various chapters do. The exception to this rivalry is the legendary First Company, the Justaerin. Each chapter is responsible for maintaining their own relics such as terminator armor, but only the most elite of these veterans are selected to join the glorious First, whose numbers are never greater than five hundred, in memory of those five hundred who fought on Luna so long ago. In addition, those who join the Luperci are forever barred from entering the Justaerin or Mournival, for theirs is a fate apart.

The size of the Warmaster's legion is primarily a result of the incredible purity of its gene-seed, the greatest of all the loyal legions. In contrast to the Sixth or Eighteenth Legions, Horus's genetic legacy has always been incredibly easy to implant, and as such the legion has maintained high numbers through the millennia. They maintain all functional Astartes organs, and the only defect is a predilection towards resembling their fallen primarch. For whatever reason, these so-called "True Sons'' have their facial features change as the years pass, losing their hair as they grow to appear like Horus did so long ago. Examples of this phenomenon were present even during the Great Crusade, most notably from Fifth Company Captain "Little Horus" Aximand. The current Legion Master, Imset, is one of these True Sons, and it is said legionaries bearing the phenotype are blessed by Horus himself.

Warmaster Imset

The legion masters of the Sons of Horus are almost always selected from amongst the ranks of the Mournival, though they step down from the office when they assume command. However, this is not always the case, as evidenced by the current legion master, Djoser Imset. Imset has been the master of the Sixteenth Legion for nearly nine centuries now, after the death of his predecessor Haarken Duamutef during the 12th Black Crusade. Imset is estimated to be one of if not the oldest Space Marine alive, not counting dreadnoughts, and is truly a hero among heroes.

Imset is a master of every form of war, and has led the legion to innumerable victories. Yet it is his temperament that has gained him the love and admiration of the Imperium. Imset has inherited his primarch's legendary charisma, and is close to the common people like few others. He shoulders their burdens, and weeps for their losses. The legionaries under his command say he is more likely to die of a broken heart than in battle, for his victories are beyond counting. As M41 draws to a close, Imset has brought his forces to bear in defense of the Cadian Gate, and stands ready to repel the dread forces of Sigismund who even now prepare to march on the Thirteenth Black Crusade.

Combat Doctrines and Organization

The Sons of Horus have retained the same combat doctrines that they employed since they first won their fame. The quick strike, the coup de grace, the single blow to win the battle: all these and more describe their operational style, but no title fits quite so well as the speartip. Not for them the grinding attritional warfare of the Death Guard or Iron Hands, nor the complexities of the Alpha Legion or Night Lords: the Sons of Horus prioritize one decisive blow aimed at the enemy's command structure. The speartip tactic has won them victories innumerable for ten thousand years. From tyranid synapse creatures to ork warbosses to Chaos champions, every foe collapses when its leaders are defeated and thus showing their followers the weakness of their cause. However, the speartip is a flexible structure, and should the initial strike be stopped, its members are fully capable of splintering into smaller groups, each continuing the mission to either its conclusion or their deaths.

However, the Sons of Horus learned long ago that such tactics can be turned against them. The scars of the Eternal Fortress still burn thousands of years later, and the Sixteenth Legion has learned not to put too much pressure on one leader. None shine as brightly as their father, the original Warmaster, and each subsequent Warmaster swears a solemn oath to honor the mantle they have inherited. Warmasters of the legion are privileged to bear the mantle of office, selecting to wield either the maul of their primarch, the mighty Worldbreaker, or the deadly lightning claw known as the Talon of Horus. Legion rumors say that one day a hero will arise worthy of wielding both weapons in tandem, but as of yet no Warmaster has dared claim it for themselves. The legion maintains not only the title of Warmaster, but also the office of Mournival.

After the utter slaughter that was the Siege of Terra, only Hastur Sejanus still lived of the four Mournival Lords. Though he was reputed to have mastered all four of his humors, he was still one man, and no man is perfect. Had Horus appointed other Mournival members to replace the fallen, perhaps they would have been able to prevail upon their father not to pursue vengeance, and perhaps Horus would not have perished at the tip of the spear. Sejanus recognized this, and after regrouping his forces upon Cthonia after the conclusion of the Eternal Fortress campaign, he named new Mournival members to replace him before joining the Luperci. Originally Sejanus desired to renounce his rank after leaving the Mournival, but the wisdom of his brothers prevailed, and he acquiesced, remaining as leader of the legion until his eventual death. Since then, the Sons of Horus have been led in the same fashion with one leader and his four advisors. Most Mournival advisors are taken from the ranks of the senior chapter masters of the legion, but there is no law saying it must be so. Indeed, some of the legion's greatest heroes have come from other paths, such Corpulax, a promising Apothecary, or Eralak, who was only a sergeant in an Assault Company when he was selected. Potential Mournival members are not required to join, though few refuse such an honor. One such recusant was Captain Obsidius Mallex, of the Servants of the Abyss Chapter.

Obsidius Mallex

The gang traditions of Cthonia bind all members of the Sons of Horus, and just as few gang members would dare to disobey the word of their superiors, so too do few Astartes go against the commands of their sergeants and captains. However, some Astartes are possessed of more independence than deference, a rare balance of humors that often gets the individual in trouble. Yet such a personality also marks them for potential Mournival membership, for Warmasters of the legion seek advisors, not yes-men.

From his entry into the legion in 847 M41, Mallex quickly became known as a troublemaker and rebel. He showed particular affinity for void warfare, and led many successful operations against pirates in the Cadian Sector. Unfortunately, it was during one of these operations that Mallex was lost. What looked to be a simple pirate ship turned out to be a scout from the Black Templars, and in the ensuing combat, its Warp engines overloaded, sending Mallex and his ships into the Warp. Warmaster Imset held out hope that Mallex may return, but after ten years, he was declared missing in action.

In addition to the office of Warmaster and Mournival, the Sixteenth Legion has maintained the same basic structure as it did during the Great Crusade with slight adjustments. Instead of the mere advisor status that it once held, the Mournival now wields high authority, and each is in command over a number of chapter masters that report to them. Thus the Warmaster is able to look at the bigger picture, while his Mournival suggests which chapters might best be suited for a particular mission. Each chapter is composed of varying numbers of companies, though most possess high numbers of dedicated assault troops. Other legions such as the Blood Angels or World Eaters, those that specialized in storming operations and rapid assaults, turned their backs upon the Emperor, and so the Sons of Horus remain without equal among the loyal legions when it comes to shock assaults.

Many legions bear signature weapons, tools of war that they have mastered in a way that puts their cousin legions to shame. In the indomitable Death Guard, the scythe holds special place, while the dread Space Wolves are unique in their usage of Helfrost weaponry. The Sons of Horus are no different, though their weapon of choice is far simpler: the power knife. All legions bear the power sword, and see little point in a smaller version of the same weapon. Yet these power knives hold a special place in every son of Cthonia. The hive-world's gangs are fierce fighters, deeply distrustful, and thus they carry their knives everywhere. When these gang members are inducted, their knives are reforged, the cheap steel coated with adamantium and equipped with a power field that it might pierce any armor. Every legionary carries such a knife, even Warmaster Imset, and if possible, they will bear it until the day they die.

Perhaps because of their fierce and independent nature, it is the Sons of Horus greatest shame that their chapter has given rise to more traitor warbands than any other legion. Though they are relentless in screening Cthonia for signs of Chaotic corruption, the sheer number of tunnels and warrens means the darkness is always present. Traitor warbands have plagued the Sixteenth Legion since the Heresy itself, when a portion of the legion was captured upon Davin during the Great Betrayal. These Astartes, led by a legionary or perhaps a series of legionaries known only as Ygethmor, have remained elusive figures, opposing the legion throughout the millennia as they corrupt and tempt the foolhardy legionaries sent to destroy them. When such treachery is discovered, their companies are stricken from the rolls of honor, their deeds of valor erased from the records, and names given to the Luperci, to be destroyed at the earliest opportunity.

As heirs of the Warmaster and the largest legion, the Sons of Horus maintain extensive diplomatic relations within the Imperium. Among their fellow legions, they are closest to the Raven Guard, and maintain a friendly rivalry with the Space Wolves. They maintain good relations with the other six legions, as well as a close relationship with the Imperial Guard, who are frequently called upon to act as the second wave to their speartip operations. They maintain positive relations with the High Lords of Terra, and are frequently called upon for important tasks. Slightly strained relations exist between them and the Ecclesiarchy, for the Imperial Truth is still upheld by all but a few chapters of the Sixteenth Legion. Likewise, the Mechanicus see the Sons of Horus as too driven by emotions, so interactions between the two are kept to a minimum.

The Sons of Horus most often fight against xenos. They have but rarely fought against the tyranids, but frequently clash against Orkish hordes, battles that occur ever more frequently as the years pass. When the War of the Beast occurred in M32, the Sons of Horus took heavy casualties when Cthonia itself came under assault from a war moon, though the legion inflicted far more in return, honoring the memory of their forebears at Ullanor centuries before. However, they are just as adept at fighting Chaotic incursions, and have clashed many times with the forces of various Black Crusades. Of all the traitor legions, the Ninth Legion are the traitors who hate the Sixteenth the most. Horus's twin victories over Sanguinius infuriate the Daemon Primarch, and his death at the hands of Perturabo means he will never be able to defeat the Warmaster in combat. Thus his sons seek to revenge themselves upon the Sons of Horus, and the two legions are sworn rivals. However, the rivalry is somewhat one-sided, for the Sixteenth despise the Iron Warriors and the Dark Angels far more. The sons of Perturabo are hated for their role in the Warmaster's death, and the two have clashed many times over the millennia. Almost as intense is the rivalry with the Dark Angels. The First Legion is recognized as the architects of Heresy, and the Great Treachery upon Davin has left the Sons of Horus always eager to destroy their hated foes. For their part, it is believed the Dark Angels envy the Sixteenth for their title of Warmaster's Legion, but little is certain where the Dark Angels are involved.

Beliefs and Warcry

Like other legions, the heart of the legion's culture is kept within the halls of the Fortress-Monastery. Cheops itself is rarely filled to capacity, for most chapters stay out on campaign save for the few times they are called back, but even out in the stars they still maintain the gang traditions of Cthonia. Many warriors bear tattoos symbolizing their allegiance, complex symbols and patterns that show clan and company. In addition, some warriors will ritually mark themselves to commemorate a great victory or tragic loss.

Much like the Salamanders keep records of their legion within the Tome of Fire, the Sons of Horus maintain their own ledger. Known as the Book of the Dead, this vast cavern located deep within Cheops is a maze of walls made of the last remaining ore dug by hand far below Cthonia's surface, as well as the shattered remnants of power knives from legionaries who have died in service to the Emperor. Inscribed upon these stones are the names of every legionary who has ever borne the gene-seed of Horus, and when they die, their knives will be melted down and added to the wall that their legacy might live on. When inducted into the legion, the aspirant is escorted by the Luperci to the chambers, and given a chisel to carve out their personal glyphs by hand upon a designated section of wall. The stone dust is then taken and molded into a small trinket, a symbol of Cthonia to be taken with them everywhere, and a true son of Cthonia would rather die than be parted with it.

The Sixteenth Legion has gone through multiple armor colors during its long and storied history. Like all legions, their initial colors were unmarked gray. Later on, after becoming the Luna Wolves, their armor bore the white and black symbolizing the two sides of Luna itself, while their shoulders bore a wolf's head. When Horus was named Warmaster and his legion became the Sons of Horus, their colors and symbols were changed once more. Since that day, the Sixteenth Legion has borne a murky verdigris of teal, with highlights of black and orange. The Eye of Horus, once reserved for the primarch himself, has become a badge of honor for the legion as a whole. During the fires of the Leonine Heresy, a common way to mark oneself as loyal to the Imperium was the Imperialis, the symbol of the winged skull born upon the breastplate. In the Sixteenth legion, however, the central skull is replaced by the Eye of Horus.

The fierce nature of the Sixteenth legion means they have many warcries. Only the Luperci fight in silence, utterly focused upon the destruction of the enemy. The senior officers and Mournival most often fight with the cry of "Kill for the Living and Kill for the Dead!". Others, remembering their Luna Wolves roots, will howl, a truly terrifying sound coming from hundreds of posthuman warriors. However, there is one cry that binds all Sons of Horus: "Lupercal". Be it at the feast hall or the battlefield, the Sixteenth Legion keep their father's memory alive and honor his legacy forevermore.

M32

The Eternal Fortress. What a joke. Only a man lost to his own madness or that of the Warp would tempt fate with such a name. And fate had come, for now it was but ruins, rubble for my children to pick through. The Corpse Grinders had never been subtle in their ways of war. Atomic fire had scoured these ruins, and I feared there might not be anything left of value.

The moaning of one of my former brothers drew my attention. Once a proud warrior of the Third Legion, the Blight had left him a shell of his former self, until I made him new once more. I walked over to where the creature stood, hunched above a gore-slicked slab of duracrete. My Chirurgeon clicked as its spidery limbs leaned over my pauldrons, taking samples of the tissue and analyzing it.

My helmet display flashes green, and I can't help but smile. What luck, living cells from a primarch! And not just any primarch: these were from the famous XVI. Though his barbarian sons would no doubt disapprove of my work, they should be thankful, for through me Lupercal himself will live once more. I patted my child on his head, and he growled back in contentment. Gathering as much of the sample as I could, I signaled the dropship to return us to the Sepulchritudinous, for there was much work to be done, much work indeed.

A/N: At just over 22k words, this entry far surpasses my earlier works, and it worries me how long the Dark Angels index will be when I finally get there. Horus is as close as you can get to the main character of the 30k era, it's his actions (both in canon and my timeline) that make others react, and thus this entry is much longer than the others so far. As always, please comment on what you did and didn't like, your guesses for the future, and if you spotted references, because they're definitely in there. Next up will be the Thousand Sons, my first Chaos entry, and I hope to see you all there in the future. Sharrowkyn, out.