Mortarion

"Pain is an illusion of the senses, fear an illusion of the mind, beyond these only death waits as silent judge o'er all."

- Primarch Mortarion

Mortarion, also known as the Death Lord or the Prince of Decay after he turned to Chaos, was one of the original twenty Imperial Primarchs created by the Emperor of Mankind. He was given command of the Death Guard Space Marine Legion on the arrival of the Emperor to his homeworld of Barbarus, but he turned to the Forces of Chaos during the Horus Heresy. At present, Mortarion is the greatest Daemon Prince of Nurgle and the Daemon Primarch of the Death Guard Chaos Space Marines.

Childhood
When the twenty Primarchs of the Space Marine Legions were scattered across the galaxy in a mysterious accident, one came to rest on the planet Barbarus, a world wreathed in poisonous fog. The population of the world was split into two groups: the controlling warlords; necromancers with fantastic powers along with the human settlers, who had been trapped on the planet millennia before and were now forced to eke out an existence in the poison-free valleys of the planet, fearing the wrath of the warlords and their creations.

The Primarch-child was taken in by the most powerful of the warlords, who found him amongst the corpses of a battlefield, screaming and wailing where a normal child would have suffocated and died long before. The Overlord of Barbarus took the child in with the intention of creating a son and heir, naming him Mortarion - child of death.

Mortarion was kept in a fortress positioned at the limit of even his superhuman tolerance to the toxins in the air, while the Overlord moved his own fortress to the highest peak of the world, beyond where even Mortarion could go. He trained the child, who had a highly keen intellect and voracious appetite for knowledge; Mortarion learned everything from battle doctrine, to arcane secrets, from artifice to stratagem. However, the young Primarch's questions began to turn towards subjects the Overlord did not want to talk about, namely the pitiful creatures in the valleys that the many warlords preyed upon for corpses to reanimate and bodies to warp.

The Deliverance of Barbarus
Finally, knowing he would be unable to find the answers he desired from his adoptive father, Mortarion broke out of the fortress that had been his home and prison after killing several guards stationed at the gates of the fortress, and headed for the valleys of Barbarus. Breaking through the poisonous mists, Mortarion discovered that the prey of the warlords were in fact the same species as he, and swore to deliver them from their oppression. The people of Barbarus were slow to accept this pale, gaunt stranger from the mountains, but Mortarion was given a chance to prove his worth when creatures enthralled to another warlord attacked the village. Seeing that the peasants were unable to effectively fight back, Mortarion joined the fray, wielding a massive harvesting scythe that made short work of the beasts. The warlord smiled when Mortarion advanced upon him and withdrew to the apparent safety of the deadly fog, only to be pursued and butchered by this inhumanly resilient Primarch.

Accepted into the village without further reservation, Mortarion began to train the villagers in the art of warfare. Soon, representatives from other villages journeyed to learn from Mortarion, while the villages scattered across the valleys of the world were transformed into strongpoints. Mortarion travelled from settlement to settlement, teaching, building and defending his people.

He recruited the toughest, most resilient men he could find, forming them into small units that trained under his supervision. He enlisted the aid of blacksmiths, craftsmen and artificers to create suits of armour that would allow men to travel through the poisonous fog. As each battle in the mists was fought, Mortarion and his Death Guard would learn how to better adapt the armour, and themselves, to reach the more poisonous heights. Eventually, only one peak denied them access, the one on which Mortarion's adoptive father had made his home.

The Coming of the Emperor
Despite his adoptive father being a ruthless necromancer, Mortarion felt reluctant to attack the man who took him in and called off the planned attack. Returning to the village, Mortarion's mood darkened when he found his people talking not of his victory but of the arrival of a benevolent stranger who promised salvation to the people of Barbarus. Finding this stranger in conference with the village elders, Mortarion claimed that his people needed no outside help. The stranger commented that even Mortarion and his Death Guard were having trouble pacifying the final warlord, and offered a challenge. If Mortarion could defeat the Overlord, the stranger would leave. If not, Mortarion had to swear fealty to the stranger and the Imperium of Man he represented.

Ignoring the protests of his Death Guard, Mortarion left alone to confront his adoptive father, motivated by a compulsion to prove himself to the stranger below. The confrontation was brief. The air surrounding the Overlord's fortress was so poisonous, that parts of Mortarion's armour began to rot. He collapsed at the gates of the Overlord's citadel, bellowing challenges. The final thing Mortarion saw before he blacked out into unconsciousness was the Overlord of Barbarus coming to kill him, then the stranger leaping between the two and slaying the Overlord with a single sword thrust.

When he recovered, Mortarion swore fealty to the stranger, who revealed himself to be Mortarion's father, the Emperor of Mankind. The Emperor granted Mortarion command of the XIV Space Marine Legion, then known as the Dusk Raiders, who quickly adopted the name and dogma of Mortarion's Death Guard. However, The Emperor's slaying of his adoptive father proved to become a grudge Mortarion long held against him.

A Mournful Unity
True to his oath, Mortarion bent his knee to his new-found father as soon as he was sufficiently recovered to do so, although his final act of defiance on Barbarus would leave scars upon him both physical and mental that would never fully heal. A skilled warlord in his own right, Mortarion was immediately given command of the XIV Legion of Astartes which carried his genetic inheritance, and did so on his own terms. Gathering them before him, a grim and spectral figure robed and bearing the great black scythe that had once belonged to his nightmarish foster-father, it must have seemed to the Terran-born Dusk Raiders that an ancient, graven image of the Grim Reaper had come before them as their new master. His words were simple and delivered in a harsh whisper that never the less carried to each and every one: "You are my unbroken blades. You are the Death Guard. By your hand shall justice be delivered, and doom shall stalk a thousand worlds." The Legion's name was then changed in accordance with this decree, and Mortarion's words were engraved above the airlock door of the Battle Barge Reaper's Scythe in honour of that moment. By this simple decree the Dusk Raiders were no more, and the records and annals from that day forward would carry this new name as one to strike fear into the hearts of Mankind's enemies.

The XIV Legion's Astartes had been primarily Terran-born before Mortarion joined the Legion; after that time almost all of the Legion's Neophytes were drawn from the Feral World of Barbarus. This changed the culture and traditions of the Legion, so much so that by the last days of the Great Crusade in the early 31st Millennium, there were increasing tensions between the Barbarus-born Astartes and the Terran minority who remained in the Legion and who remembered the Dusk Raiders' earlier martial traditions brought out of Old Terra. These tensions became most clear in the period directly preceding the first battle of the Horus Heresy at Istvaan III, when approximately one-third of the Legion was judged by Mortarion to be likely to remain loyal to the Emperor when the Legion joined the Warmaster Horus in his rebellion against the Imperium. Many of these Loyalist Death Guard Astartes were Terran-born, former Dusk Raiders like Battle-Captain Nathaniel Garro of the 7th Great Company whose loyalty to the Emperor outweighed their devotion to their Primarch.

The Great Crusade
"Say what you like about the Fourteenth Legion. They are mean, ugly bastards but tenacious. There's no one else I'd rather have by my side in a war of attrition, and almost anyone else I'd rather have against me."

- Ferrus Manus, Primarch of the Iron Hands Legion, after the compliance of One-Five-Four Four

In the decades that followed the renamed XIV Legion fought tirelessly in the service of the Great Crusade. Never relenting in battle beneath their Primarch's gaze, they pursued the liberation of Mankind with a fervour the Great Crusade had never known. Their restless fleet ploughed the cold void from one campaign to the next, resupplying on the move, never pausing but to make war. The Death Guard did not garrison, they did not build, they only tore down and slew, coldly, determinately and with the inexorable progress of a contagion or a tsunami wave, and worlds fell before them.

Over time Mortarion shaped the creed and practice of the Death Guard, his beliefs in many ways forming a natural extension of their own, beliefs and doctrine becoming ever more refined and extreme. At the heart of them was the unshakeable determination that Mankind should be free of oppression and terror. Such freedom could only be won in the Primarch's mind by destroying those that would shackle and devour humanity. This was a war to be fought without mercy or limit, without restraint or relenting. The battle for the human future was one that could only be won by enduring any hardship, no matter how terrible, and not shirking from any act, no matter how savage in pursuit of victory. This single end, the liberation of humanity to Mortarion's creed, justified any means.

Mortarion believed that victory in battle came through sheer resilience, and Horus, who used the strengths and weaknesses of the different legions to create the most efficient fighting force possible, used his legion in co-ordination with Mortarion's frequently. Mortarion and the Death Guard would draw out the enemy and tire them down, and then the Luna Wolves would strike. This combat tactic worked brilliantly, and Mortarion grew close to Horus.

Mortarion was a grim and driven Primarch, his breathing apparatus and scythe an inseparable component of his aspect. The pallid, hairless Primarch was viewed by others as a freak, and was distant from all his brother Primarchs save Horus the Warmaster and Konrad Curze the Night Haunter, the leader of the Night Lords Legion. Some Primarchs, such as Roboute Guilliman, feared that Mortarion was more loyal to Horus than he was to the Emperor; however, at that time, the Emperor claimed that loyalty to Horus was de facto loyalty to Himself. Events would prove the Emperor sorely mistaken.

The Inheritance of Barbarus
Decades of endless battle changed the Death Guard, and over time the Terran influences on the Legion became less and less apparent, with the panoply and traditions of the Dusk Raiders and the Officio Militaris erased in favour of Barbarus' bleak creed of war. The bare ivory-grey unpainted ceramite that Mortarion favoured for the Legion's Power Armour became increasingly less adorned, save for new murky-jade markings set to echo the corrosive-resistant swamp mud applied to coat the iron plates of the human warriors that had once served the Primarch of Barbarus, and shorn of older heraldry and Terran influence. The martial stratifications of Old Earth's warmasters were done away with too, and eventually the XIV Legion's Librarius was disbanded thanks to Mortarion's hatred of witchery such as that the hated charnel masters of Barbarus had once wielded.

Mortarion's hand and mind was at work everywhere remaking his Legion, from changing tactical doctrines to equipment procurement and, some say, behind the selection of candidates and changing practices in the Legion's Apothecarion, where he gained the latter knowledge to interfere. With the prevailing conditions on Barbarus and the foul beings that more than likely still stalked the planet's fog-shrouded mountains and deep swamps, there were whispers that the human population that remained would have been better off if they had been euthanised or displaced to a "cleaner" world for the sake of the sanity of future generations. Mortarion would have none of this, for Barbarus now belonged to his people, bought and paid for by generations of blood and terror, and its strongest sons would now serve as recruits for his new Death Guard.

As for the purely human Death Guard that had once fought for him against the overlords of Barbarus, many now became the masters of that world and a dread aristocracy they soon became, while the youngest and strongest took full or partial conversion into the Legiones Astartes, heedless of the high fatality rate that late induction carried with it. This was deemed a small enough price to pay to continue in the service of Mortarion their saviour. With new recruitment at issue, Barbarus itself in a short span of Terran years became little more than a factory of sorts to produce new recruits for the Death Guard Legion, and intake from other sources of recruitment to which the Legion had title dwindled to a mere handful, unless the pressure of fatalities in the field proved too great. Mortarion's resistance to the use of bloodstock other than that of Barbarus wavered only because of the need to keep his Legion's strength battleworthy in his eyes. Recruitment solely from Barbarus was however aided by the high suitability of the planet's hardy feral population to the conversion process. The Legion's gene-seed seemed to amplify the uncommon resistance to contagion and toxins in its Barbarus candidates to unheard-of levels.

As fresh intakes of new Space Marines came in from Barbarus, the surviving core of Terran blood became a minority as the Great Crusade burned on across the stars, the Death Guard at the forefront of the fighting in the most hellish war-zones imaginable. Although second perhaps in their father's eyes, the Terran contingent remained stubborn in the ranks, hardened veterans and a force to be reckoned with in the Legion. With the Legion drawing the majority of its Neophytes from Barbarus, this changed the culture and traditions of the Legion, so much so that by the last days of the Great Crusade in the early 31st Millennium, there were increasing tensions between the Barbarus-born Astartes and the Terran minority who remained in the Legion and who remembered the Dusk Raiders' earlier martial traditions brought out of Old Terra. These tensions became most clear in the period directly preceding the first battle of the Horus Heresy at Istvaan III, when approximately one-third of the Legion was judged by Mortarion to be likely to remain loyal to the Emperor when the Legion joined the Warmaster Horus in his rebellion against the Imperium. Many of these Loyalist Death Guard Astartes were Terran-born, former Dusk Raiders like Battle-Captain Nathaniel Garro of the 7th Great Company whose loyalty to the Emperor outweighed their devotion to their Primarch.

Council of Nikaea
Mortarion was present at the Council of Nikaea, where he spoke out against his brother Primarch Magnus the Red. Having witnessed during his youth on Barbarus the horrors produced by psykers, he testified against them, ending his plea with a dire warning against any use of sorcery by the servants of the Emperor. Unlike the other speakers at Nikaea who stood against the use of psychic powers and who mostly harangued Magnus and reviled the Thousand Sons but brought little proof or argument to the debate, Mortarion's intervention was short, impersonal and to the point. It therefore made a great impact upon the opinion of the Emperor, and drove Magnus to defend the use of psychic abilities with more drive and passion than he had originally intended.

The Horus Heresy
"There is no darkness to be found between the void of stars, nor the deepest pits of the earth that equals the darkness of Mankind's deeds."

- Excerpt from the suppressed Neo-Terran Credos

When the Warmaster Horus turned to Chaos, he did not require much effort to drag Mortarion and his Legion down with him. Horus had been one of the few Primarchs with whom Mortarion had felt comfortable, and as such he showed more loyalty to the Warmaster during the Great Crusade than to the Emperor Himself. In addition to this, First-Captain Calas Typhon, Mortarion's right-hand man, had long been a secret follower of the Ruinous Powers and eagerly manipulated the rest of the Death Guard into treading the path of damnation. Mortarion revealed his true colours during the scouring of Istvaan III, when he willingly sent potentially Loyalist elements of the Death Guard into Horus' trap. Once the Astartes who remained loyal to the Emperor were purged, the Death Guard then fought alongside their Traitor brethren during the Drop Site Massacre on Istvaan V.

The Warhawk and the Death Lord
For much of the Great Crusade, the errant White Scars Legion under the command of Primarch Jaghatai Khan had remained noticeably absent from the current chain of events that were only now beginning to trickle in to their fleet's Astropathic choirs. As they interpreted the astropathic messages they received in a contradictory manner, they began to suspect that things were not right. It had begun in the Chondax System, right towards the end of the campaign against the Greenskins -- the first inkling that all was not well. There had been no detail then, no authentication, just stray astropathic messages of dubious provenance. It should have been easy to dismiss, to put down to the warping power of the Empyrean. But it had worn on the Khan, unravelling his sleep. Jaghatai was next contacted by the Space Wolves' Leman Russ who had just returned from the Burning of Prospero and the assault against the Space Wolves' old rivals, the Thousand Sons Legion. The VI Legion's fleet had mustered at the Alaxxes Nebula to lick its wounds after the recent campaign, when it was beset by the forces of the Alpha Legion. Although the Khan sympathised with the Space Wolves' predicament, he refused to get involved until he was able to sort out the conflicting and often contradictory astropathic messages he had received. Until he knew, beyond a shadow of doubt, who was ally and who was an enemy, he refused to choose sides. Wishing his brother the best of luck, Jhagatai wished to seek his answers elsewhere.

The White Scars fleet made all haste towards Prospero, the recently ravaged homeworld of the Thousand Sons Legion. The Khagan ordered his Legion to head for the source, to find the architect of the chaos engulfing the Imperium. Yet, only one soul could see the Warp as it truly was, and that was Magnus the Red, the only one of his brothers that Jaghatai had ever truly trusted. If Magnus yet lived then everything could be salvaged. If he was dead, then the Imperium was finished. Eventually the Khan found the answers he sought in the crystal caves deep underground, beneath the destroyed capital city of Tizca. When he made his way back to the surface of the planet, he next encountered an unexpected visitor. As the clouds above them began to glow, a vibrant shard of light speared down from the smog, crackling as it hit the stone below. The Terminators turned to face it, powering up their weapons. Jaghatai told his bodyguard he had felt this new arrival's presence following them for a long time. He had been on the Khan's heels since Ullanor. At long last he had finally caught up. The Khan ordered his warriors to stand down, for the stranger was beyond all of them. How could he not be? For it was his brother -- Mortarion, the Death Lord, Primarch of the Death Guard Legion. Watching the ash settle and the residual snags of aether-burn ripple into nothing, seven figures within the maelstrom emerged. Six of them were Legionaries. They were clad in pale, thick-slabbed Terminator Armour and carried huge Power Scythes known as Manreapers. Their pauldrons were olive-green and the links between the plates were cold iron. They were massive, heavier-set than the Khan's retinue, hunched at the shoulder and leaking pale green vapour from the last of the teleportation beams. These were members of Mortarion's elite bodyguard, the Deathshroud.

Mortarion proceeded to explain the reason for his recent arrival; he told Jaghatai that he had sought him out, for things had changed. Jaghatai realised that his brother had come to persuade him to join the Traitors' cause. The Khan observed him guardedly, for Mortarion had always been hard to read. He left his blade unsheathed, holding it loosely at his side. Observing the physical changes in his brother, he noticed that Mortarion's power seemed to have grown. Something burned in him, dark like old embers. His flesh was somehow bleaker, his stance a little more crabbed, and yet the aura of intimidation around him had been augmented. Back on Ullanor, even at the height of triumph, he had not possessed quite the same heft. Jaghatai commanded his brother to say what he had come to the ruins of Prospero to say. The Khan correctly surmised that Horus had not sent Mortarion, he had come of his own accord, with his own agenda. Mortarion brushed off the Khan's reasoning, but Jaghatai pressed him. The Death Guard Primarch attempted to sway the Khan to Horus' cause, to imagine a galaxy of warriors, of hunters, where the strong were given their freedom to act as they would, unbound by the Emperor's demands. The Khan was no fool, of course this new galaxy would all be led by Horus. Mortarion merely shrugged -- Horus would be the start of the new order. He was the champion, the sacrificial king. He might burn himself out to get to Terra, he might not. Either way, there would be room for others to rise to power over the galaxy to come.

Mortarion told his brother that he should not have thrown in his lot with Sanguinius, let alone Magnus. He hated to see the three of them getting dragged in deeper by the Emperor's hypocrisy. Their father had tried to pretend that it was not there, the Warp, as if He were not already up to His elbows in its soul-sucking filth. In Mortarion's opinion it should have been cordoned off, put away, forgotten about. But the Khan was not fooled by his brother's sincerity. He had seen what had happened. The Death Lord had never hidden what he wanted. Jaghatai could see how his brother thought it would all play out; first hobble the sorcerers. Silence the witches. Drive them out, and rule would pass to the uncorrupted, the healthy. This was Mortarion's great project. He had even told the Khan on Ullanor. The Khan had thought back then that they were empty threats, but he should have known better. Mortarion did not make empty threats. But it had all gone wrong. Though Mortarion had completed his great mission and the Emperor had handed down the Edicts of Nikaea forbidding the use of sorcery and the disbandment of the Legions' Librarius, there were now more sorcerers than ever amongst the ranks of the Traitors. Horus had sponsored them, Lorgar had shown them new tricks. If Magnus had not already made up his mind on which side of the conflict he would be on, then he soon would, and then Mortarion would be surrounded. He had destroyed the Librarius of the Legions only to find witches were now untrammelled amongst the Traitors.

The Khan had seen the overall picture perfectly. Magnus' shade had showed him. Jaghatai warned his brother that though his Legion might be free of the Warp's corruption for now, the change would come, for Mortarion had made his pacts with the masters of the Empyrean, and now they would come to collect. But this was why Mortarion had come to find Jaghatai. Mortarion had run out of friends. Who would stand with him against the aether-weavers now? Most assuredly not their brother Angron, nor the half-mad Konrad Curze. The Khan gazed at Mortarion disdainfully. His brother had tasted the fruits of treachery and found them bitter. The Khan did not wish to be dragged into his brother's ruin -- Mortarion was on his own. Struggling to contain his anger, Mortarion warned the Khan that he had come to give his brother a choice -- half of the White Scars Legion had already declared for Horus, and the others would follow wherever the Khagan ordered them. Their father's time was over -- the Khan could either be a part of the new order that replaced him or be swept aside in its wake. The Khan merely smiled -- a cold smile, imperious in its contempt. He would not countenance a new Emperor -- neither himself or his brother. Jaghatai explained that the reason neither one of them would ever rule the galaxy is that both of them were never the empire-builders. They were the outriders. Mortarion had chafed at this role, while the Khan had embraced it. Enraged, Mortarion backed away, Silence crackled into life, sparking with green-tinged energy. The Deathshroud lowered their scythes in a combat posture. Behind the Khan, the keshig readied their blades. The Khan prepared to settle their argument once and for all.

The two Primarchs circled one another, prepared to finally engage in a deadly duel that would decide their fates. As the two demi-gods battled, their respective retinues also fell onto one another in deadly close-combat. The silent Deathshroud were just as implacable as their master, as they fought the White Scars keshig amidst the wreckage. Warriors of both sides had already fallen, their bodies caked in the thickness of blood and dust, but the dispute raged on, bitter and unyielding. The two Primarchs traded deadly blows, tearing into one another, each strike powered by raw defiance. As they hacked and countered, neither giving up a single measurement of ground, it mingled upon the blades' edges, as rich and dark as wine. Summoning up one last burst of energy, the Khan held position, panting hard as he dragged out the remnants of his power for the final clash. In response, Mortarion only stood, rigid, as though suddenly listening for something. His scythe fell into guard and a thin coughing broke from his mask, which the Khan realised was an exhausted kind of chortle. "So the choice has been made."

Mortarion informed Jaghatai that their respective starships were at war. This was not what they had been promised by the White Scars' Warrior Lodge brothers, but the Death Lord refused to lose a fleet for this fight. Feeling the dust stir around his feet, coils of marsh-green teleportation energy rippled downward. He saluted the Khan mockingly, and spears of hard-edged light lanced down from above, bursting through the cloud cover and crashing through the heart of the ruined Tizca pyramid they had been fighting within. The Khan sprang forward, seeing too late what was happening. In an instant, the Death Lord and his retinue were snatched away, sucked into the vortex of the Warp. The world's wind howled in their empty wake, ash stirred and the lightning forked. Jaghatai, carried by the momentum of his final thrust, staggered though the empty space where his brother turned enemy had been.

Seeking Answers
Chagrined by his defeat at the hands of Jaghatai Khan, Mortarion abandoned the pursuit of the White Scars and instead lead his Death Guard in a spiteful, punitive rampage across the systems of the lost Prosperine empire. World after world soon fell to this horrific onslaught, and yet the insular and secretive Primarch seemed preoccupied by some other, unspoken goal. Finally he found what he sought for upon the world of Terathalion, a former library-world where knowledge coalesced, all under the benign guidance of distant masters on Prospero. When his voidships emerged from the Mandeville jump point in the Imperial year 007.M31 and spread out through the local system, they were not the sleek and gloriously decorated crimson-coloured system-runners of Magnus the Red's XVth Legion, but corpse-grey, vast-hulled leviathans. Moreover, it was no mere squadron that had arrived, but an entire battle group. Mortarion ordered the orbital bombardment immediately. When the bombardment finally relented, the few survivors crept slowly from whatever refuge they had been able to find. Thinking for a moment that the worst was finally over, they soon saw dirty contrails of Drop Pods split the smoke-barred skies. The entirety of the Death Guard Legion had come to the doomed world. Though still gravely wounded and in deep pain, the Death Lord teleported down to the surface, seeking a mortal woman. Upon discovery, he had his captive teleported with him back aboard his flagship, Endurance. Within his private quarters he interrogated the woman, who in truth, was a Daemon in possession of the woman's body. Mortarion had never encountered its kind before, believing his father, the Emperor, that such fell creatures did not exist. Now one of the denizens of the Empyrean stood shackled before him. The Primarch sought answers from the daemon. He wanted to know why his brothers Lorgar and Fulgrim willingly trafficked with the creature's kind. The Daemon explained that Mortarion's brothers had come to see the true order of things.

Despite all that had occurred, Mortarion still believed that all sorcery was a cancer. He still believed that they must guard against it -- push it back. After destroying an entire world in his search for answers, he yearned to know the truth about Chaos. Mortarion knew that he was now surrounded by the damned. Jaghatai had been right -- the Death Lord was on his own with them. The Aether stained everything. But he would endeavour to understand it -- to overcome it. The daemon's final task would be to show him how. The foul creature laughed at Mortarion's efforts. Like thousands of other mortals the creature had encountered over the aeons, each one was convinced that they alone could find a way to negotiate with the gods with little to no consequence. The Daemon explained to the Primarch that the Empyrean had many great forces in the Aether, and one of them had Mortarion's name etched over his rusting throne. He was still waiting, though not for very much longer. It mattered not how many trinkets the Primarch rattled or waved -- he would not be denied. He had claimed Mortarion. The Primarch was enraged at the creature's proclamation -- even his Father could not claim him. Mortarion admitted that he was guilty of patricide long before the seeds of treachery were sown in the Warmaster's heart. He had seen them all -- the tyrants, the witches, the xenos filth. Only he remained pure of it all, free of corruption. The Daemon could see through the Primarch's lies, and taunted him -- he didn't look pure to her at all.

The Daemon continued to taunt the Primarch, goading him on. If he wanted to know the truth, then it would be revealed. The creature's bonds were suddenly shattered and her human shell peeled away, revealing a glossy, insectoid true-form. Though the Primarch's physical strength was enormous, the Daemon knew that it would not help him, for she was a creature of anti-physics, held only by laws that the Primarch feared to invoke. In an attempt to resist the Daemon's brutal attack, he tore at it with his hands, still relying on the immeasurable strength in his post-human musculature. Enraged by this, Mortarion called upon his innate abilities buried deep down within him. The glorious stink of learned sorcery and hedge-magick was now pungent and inescapable. It was within him, he was using it, in spite of every protestation. As the Daemon sagged back against the wall, feeling her soul pulled back to the Empyrean, the Primarch continued to hammer her furiously with his fists, pouring out all of his fury onto the broken physical shell. She was the first to see a fragment of what he would eventually become. As the creature died, and her quintessential matter was sucked back into the maw of the Æther, she managed a mock salute, "Hail, Master of the Plague!" Mortarion stood over the crushed heap, breathing heavily. For too long, he had been used by all sides. The void now seethed with witchery, more virulent than ever. He could feel its tendrils grasping for him. The Death Lord knew he would have to learn more. He would have to master all the paths of ruin. He would, as perhaps he had known but refused to believe for a long time, have to become the very thing that he hated. "So be it," he thought to himself, "It starts here."

The Doom of the Death Guard
During the subsequent assault on Terra itself at the end of the Heresy by the Traitor Legions, the Death Guard were part of Horus' invasion force. However, en route, the entire Death Guard Fleet became trapped in the Immaterium due to the actions of First Captain Calas Typhon, trapping them in a perpetual nightmare. It was whilst on campaign with the Word Bearers Legion earlier in the Great Crusade that Typhon had learned of a different path for the Legiones Astartes to follow, a future where his hard-won but hidden psychic abilities would be a source of greatness instead of a taboo to be hidden from sight. The foremost Chaplain of the Word Bearers, Erebus, inducted Typhon into the secrets of the Seven Pillared Lodge, one of the Warrior Lodges that had begun to spread throughout the Space Marine Legions in the later days of the Great Crusade. It was during this time that Typhon caught a glimpse of what the Astartes could truly become if they shrugged off the yoke of the Emperor's ambitions.

Perhaps Typhon's revelation was instrumental in Mortarion's own fall to the Ruinous Powers; perhaps Mortarion would have walked a dark path on his own. Either way, the troubled Death Guard Primarch saw a worthy master in Horus, whereas in the Emperor he saw only a self-serving and pompous pretender who had stolen Mortarion's hard-won kingship in a single day. As the Heresy that Horus initiated slowly but surely escalated into a galactic civil war, Mortarion ordered his fleet to head for Terra with all haste, intending for the Death Guard to join the other Traitor Legions in the destruction of the False Emperor. By this point, Calas Typhon served one master alone, and it was not his Primarch. Typhon had seen to it that the fleet's Navigators were killed to a man (claiming their loyalty was still to the Emperor), but reassured Mortarion that the Warp-gift he possessed would see them through their journey in the Empyrean safe enough. Though he hated the concept of relying on witchery, Mortarion was left with little choice. The Death Guard fleet made transition into the Warp, and in the process damned themselves to an eternity of war as the puppets of a foul and ancient god.

In leading the Death Guard into the Warp, Typhon had delivered them into the clutches of his new master, Nurgle, the Lord of Decay. The strange tides of the Empyrean are notoriously fickle, and during their voyage the entire Death Guard fleet was becalmed. As their warships lingered, directionless and without hope, the cloying influence of Father Nurgle began to take hold. The Death Guard were subjected to the terrible infection of the Destroyer Plague and Nurgle's Rot, as Nurgle's power managed to infiltrate the vessels of the XIV Legion. It polluted the vessels themselves as easily as it did the transhuman warriors within. The virulent plagues infected the fleet while they drifted aimlessly through the Warp, making a mockery of the Death Guard's legendary resistance to poison and contagions. The plague that came could not be resisted, something that terrified Mortarion and the Death Guard. It transformed them into bloated mutants, yet none could die, their own body being their undoing. None suffered more than Mortarion, for it was like being on the mountain top again, surrendering to the toxins, but this time without the Emperor to save him. Eventually, Mortarion could suffer no more and gave himself to Chaos. Desperate, Mortarion offered his Legion and his own soul up to the Ruinous Powers in exchange for deliverance. Father Nurgle responded and took the XIV Legion and Mortarion for his own.

What emerged from the Warp bore little resemblance to what had gone in. The Death Guard Space Marines' once gleaming grey armour was corroded and shattered, barely containing their bloated, pustule-riddled bodies. Their weapons and armour were powered by the energies of Chaos and they became known as the Plague Marines, although they would still use the name of the Death Guard for themselves. Mortarion himself left his humanity far behind and was transformed into Nurgle's greatest mortal Champion: the Prince of Decay, the very image of death. Condemned to a deathless state of decay, the Death Guard would spread their pestilent diseases the length and breadth of the galaxy for the greater glory of Chaos.

In the end, Horus was defeated by the Emperor, but unlike the other Legions, who splintered and fled into the Eye of Terror, Mortarion's Legion, now calling themselves the Plague Marines, made an orderly withdrawal, wave after wave of Loyalists breaking themselves on the Legion. Mortarion led his forces, in an ordered formation, back to the Eye of Terror. Mortarion claimed the Daemon World known as the Plague Planet as his new homeworld and it proved to be an ideal base for launching attacks from out of the Eye of Terror into the physical universe. He shaped it so well that Nurgle promoted him to become the greatest of his Daemon Princes. Mortarion had finally gotten what he wanted, a world of his own. He ruled over a toxic death world of poison, horror and misery. For better or worse, the Death Lord had come home.

Post-Heresy
Within the Eye of Terror, Mortarion was elevated to become a Daemon Prince by Nurgle, and given control of a Daemon World, now known as the Plague Planet, which he moulded into a new and despicable form, making it a virtual copy of Barbarus, placing himself in his adoptive father's position as its chief tyrant. Mortarion is believed to still be alive in the 41st Millennium. To this day, Mortarion’s Death Guard launch their assaults through the Cadian Gate and into the galaxy beyond, sometimes in large bodies and at others lending strength to allied forces. Wherever they travel they spread the joyful, exuberant poxes of Nurgle, gifting those who would know eternal life with the choicest of the Plague God's blessings. Typhon (now called Typhus the Traveller) took a more active role in continuing the war against the Imperium by abandoning his master and striking out on his own, bringing the 'gifts' of his patron to the Emperor's followers. Typhus was especially active during the 13th Black Crusade, securing his own plague-ridden stronghold by the end of that conflict.

In an ironic twist of fate, Mortarion has become exactly like the Overlords of Barbarus he vowed to kill ten thousand years ago. He now sits in a Plague Fortress atop a tall mountain surrounded by toxic clouds, just like the adoptive father he despised in centuries long since forgotten.

Recent History
In early 901.M41, during the Battle of Kornovin, Mortarion slew Geronitan, the Supreme Grand Master of the Grey Knights Chapter. In his place, the Grey Knights elevated the hero Kaldor Draigo amidst the din of the battlefield and Draigo immediately vowed vengeance against the Daemon Primarch. Alone and unaided, Draigo smashed his way through Mortarion's bodyguard of Plague Marines, struck the ancient Primarch to the ground and carved Geronitan's name on the Daemon Prince's diseased heart. Though Mortarion ultimately escaped, it would be many long years before he could enter the mortal realm once more. Draigo's insult would not soon be forgotten, as the Daemon Primarch vowed his vengeance against the upstart mortal.

Wargear

 * The Barbaran Plate - Mortaraion's war panoply is of his own design, fusing Power Armour technology with his own lore. It is designed not only to protect him in battle but augment his own singular physiology and environmental needs, synthesising trace elements of the poisonous vapours of his lost homeworld of Barbarus to mix with the air he breathes.
 * Silence - Silence, to give it the macabre nickname favoured by its wielder, is a massive two-handed battle scythe with a blade span as long as most human warriors are tall. This formidable weapon is accounted as one of the most fearsome blades wielded by any Primarch. Since Mortarion's finding by the Emperor during the Great Crusade, there have been dark whispers that the blade is of xenos-tainted origin, and some familiar with the legend of the Death Guard Primarch's early life believe it to be none other than the weapon of the terrible charnel creature that once named himself Mortarion's "father."
 * The Lantern - The Lantern is a drum-barrelled energy blaster and the preferred sidearm of Mortarion. It is of unknown origin.
 * Phosphex Bombs - Mortarion carries a number of compact Phosphex Bombs of his own design which hang from his armour in the shape of censors.