A\N: A slightly longer chapter than I usually write. Thus begins the fall of the Imperium of Man.
Disclaimer: In this particular reality, I do not own Warhammer 40k or Code Geass.
Chapter One: The Fall of Ultramar
What Has Gone Before…
The death of the Imperium of Man had begun during the Horus Heresy, but its effects were not truly felt until Abaddon the Despoiler launched the Thirteenth Black Crusade, the latest in a series of foul crusades to spread the blasphemies of Chaos throughout the galaxy. This Black Crusade, like all those before it, was met first by the defenders at the Cadian Gate, then by the millions of Imperial troops sent to reinforce the Gate. Like all the other Black Crusades before it, the Thirteenth ended with a vigorous Imperial Navy counter-offensive that recaptured most of what Abaddon had taken. The Thirteenth, though, was different in one respect. While the Imperium still held undisputed superiority in space, the Despoiler's forces had captured most of Cadia itself.
Time passed, and the Imperium breathed easy, turning its attentions to rebuilding even as the battle for Cadia raged on. For several millennia, there were no further Black Crusades, though the threat of Chaos was still ever-present. Abaddon had seemingly disappeared, and the various sects of Chaos were too embroiled in their own rivalries to unite. Then the Fourteenth Black Crusade began, marking the event that the Imperium had long dreaded: an almost-total unification of the remaining traitor Legions under the Despoiler. The Eye of Terror opened, and a million ships flooded through not only the Cadian Gate, but the nearby Arx Gate as well. Abaddon the Despoiler, his powers expanded even further by the favors of the Chaos Gods, lead this seemingly-unstoppable charge.
The Imperium, in all its bloated might, refused to die. It had clung on to life for ten thousand years, besieged on all sides by the heretic and the xeno, and it had no intention of ever letting go. The Gothic Sector and Cadia, the initial beachheads of the Fourteenth Black Crusade, were fortified to an extent second only to Holy Terra itself, and the resulting counterattack nearly broke the back of the Fourteenth Black Crusade. As the forces of Abaddon were left reeling, the seemingly-infinite manpower of the Imperium of Man was brought to bear, as men and women were flung by the millions towards the forces of Chaos, in hopes of stemming the tide. It worked, and the forces of Chaos were kept bottled up in their beachheads for centuries.
At first, the High Lords of Terra were optimistic. The Fourteenth Black Crusade had started out stronger than any of the ones before it, but with the forces of Chaos slowly being pushed out of the Gothic Sector and the Cadia system and back to the Eye of Terror, it seemed destined to failure. But as losses mounted, the Imperial line faltered and eventually broke. Chaos flooded into the rest of the galaxy, standing victorious on world after world. Entire Space Marine chapters, entire Imperial Guard regiments, were wiped out in the futile quest to stem the spread of Chaos. Fortunately, Abaddon's reunification of the Traitor Legions was not complete, and the Fourteenth Black Crusade soon stalled on account of petty squabbles and in-fighting. Even then, the Imperium was living on borrowed time: the damage was already done, with the entirety of Segmentum Obscurus firmly under the Despoiler's control, and the Imperium's once-inexhaustible armies struggling to replenish their ranks.
By the middle of M47, during what was called the Reign of Chaos by some, the Imperium's death seemed at hand. Even while divided, the combined might of the Traitor Legions was still formidable, and they constantly battered at the gates of the Imperium as heretical cults rose up on countless worlds. The Golden Throne, having steadily fallen into disrepair, was struggling to keep the Emperor alive, and the ever-faster fading of the Astronomican's light lead to the abandonment of thousands of worlds to whatever horrors happened upon them. Tyranids feasted upon entire star systems, while Necron tomb fleets embarked on an orgy of slaughter across the Imperium. As the Imperium burned, many more were driven to insanity and heresy by the laughter of the Chaos Gods looking on.
The defenses of Segmentum Solar, however, held their ground. The Chaos fleets endlessly battered against the wall that was Battle Fleet Solar. Reinforced by the remnants of the Imperial forces once stationed in Segmentums Pacificus and Obscurus, they withstood Chaos time and time again. While Imperial forces were being pulled back in increasing numbers to defend the cradle of humanity, Chaos slowly overran the rest of the galaxy. Segmentum Tempestus was overrun in a matter of centuries, and the fleets of the Despoiler set their sights on the Ultima Segmentum, the largest of all Segmentae, making up almost a third of the galaxy. With Ultima Segmentum captured, Chaos would surround the Imperium of Man on all sides, and most of the few precious Chapter Homeworlds remaining would fall into their hands.
The sheer size of Ultima Segmentum did not make for a quick conquest, and the heavily-entrenched Imperial forces made the Despoiler's armies pay a steep price for each meter of ground they captured. A desperate military alliance of human, Eldar, and Tau succeeded in holding back the forces of Chaos, but it was clear that they could only hope to delay the enemy. Resistance was still ferocious despite this inevitability, and, by the time M47 gave way to M48, the Chaos Warmasters had yet to make significant inroads into the Ultima Segmentum, and renewed infighting amongst the Chaos forces stalled the offensive.
The first half of M48 was the False Peace, as the unified Chaos offensive had stopped for the time being. While fighting persisted on the boundary between Imperial and Chaos-held space, there was nothing on a significant scale. Imperial officials all knew, however, that the infighting would not last forever, and Abaddon was already at work quashing the various uprisings. The latter half of M48 marked the beginning of what was known as the Time of Dying. Chaos was advancing once again, and the coalition in Ultima Segmentum could hardly stop it.
When the Time of Dying began, the forces of Chaos flooded into Ultima Segmentum anew, advancing at a rate never seen since the beginning of the Fourteenth Black Crusade. In less than two hundred years, Chaos ravaged dozens of sectors despite fierce resistance. The coalition was slowly splintering, but as the forces of Chaos moved in for the killing blow, their offensive slowed, then stopped entirely. Necron Tomb Worlds all across the galaxy began to awaken, perhaps roused by the enormous concentrations of Warp energy that were the Chaos forces. The Necrons carved an enormous path of destruction throughout the Chaos lines, causing Abaddon to divert his forces to fight them. Had this event occurred just a century earlier, the Imperium would have immediately launched a massive counter-offensive. However, as early on as the height of the Reign of Chaos, the Munitorium began insisting that insufficient forces existed to mount any kind of large-scale offensive without leaving the Imperium vulnerable to attack. Thus, Imperial generals could only watch as opportunity mocked them.
Despite the unforeseen Necron interference, Chaos was only delayed for three hundred years, as Tomb Worlds ran out of targets to exterminate and returned to their slumber once again. However, the Imperium still secured an enormous morale victory, having survived to see the dawn of M49. A fresh generation of troops was now ready to fight Chaos, and the forces at Ultima Segmentum beat back the forces of Chaos time and time again. Nevertheless, it was clear that the forces of Chaos would overrun the Segmentum in time, as they threw inexhaustible legions of cultists and daemons against the Imperium.
The latter half of M50 saw a brutal stalemate at Ultima Segmentum. Chaos occupied all but a few pockets of the Segmentum, but those few pockets resisted ferociously. These pockets of resistance were the Eldar craftworlds, the Astartes chapter homeworlds, and the Tau Empire, once again bound in a desperate alliance. The stalemate would continue for several centuries, with neither side gaining a decisive advantage over the other. As losses mounted, however, the coalition slowly began to disintegrate, and the last century of M50 saw the gradual abandonment of the Ultima Segmentum. The Eldar and Tau had withdrawn their forces to better defend their own territory, leaving the Imperium to stand alone against Chaos.
Faced with a hopeless battle, the High Lords of Terra decided to withdraw the remaining forces in the Ultima Segmentum back to Segmentum Solar, where the Chaos offensive was already encroaching on the Segmentum's outer fringes. The retreat that followed was disorganized, with countless ships lost in the Warp. By the second decade of M51, Ultima Segmentum was all but abandoned by the Imperium, the sole major Imperial stronghold in the Segmentum being Macragge. The forces of Chaos, especially those of the former Word Bearers Legion, descended upon the world with the intent of wiping out the Ultramarines chapter. Thus began the Second Battle of Macragge.
Macragge, Ultima Segmentum
017.M51, Day 200 of the Second Battle of Macragge:
The din of battle engulfed Macragge, as the seemingly-inexhaustible legions of Chaos swarmed the few brave Imperial defenders. Astartes of the Traitor Legions lead the charge, their blasphemous battle cries filling the air. They had already overrun much of the planet, and showed no signs of slowing down. The skies played host to a constant meteor shower, as remnants of the Imperial Navy in the Segmentum, hastily organized and designated Battle Fleet Ultima, clashed with the Chaos fleet overhead. Debris from destroyed ships rained down from orbit, burning up in the atmosphere, as Battle Fleet Ultima continued its hopeless battle.
"Stand firm men! The Emperor is our shield! His wrath is our weapon!"
The Commissar attached to the Valhallan 409th spoke those words with conviction, but the survivors of the 409th knew otherwise. In better times, the 409th would have been over a thousand strong, shipped all over the Segmentum to battle the Emperor's enemies. These were not such times. The 409th itself was a "phantom" unit, one of dozens of ragtag regiments slapped together during the Imperium's long retreat back towards Segmentum Solar. Such regiments were organized and reorganized so often that the Munitorium had long since given up on keeping track of them all. The troopers of the 409th weren't even all Valhallans: at some point during their retreat, they had picked up splinters of a Catachan regiment as well.
"Thunderhawk away! Thunderhawk away!"
A few members of the 409th paused briefly to look up, seeing the massive aircraft lift towards orbit. Those Thunderhawks, or what they were carrying, more accurately, were the entire reason several precious Imperial Guard regiments had been diverted from their march towards Terra to defend Macragge. Each Thunderhawk that reached orbit meant dozens more Space Marines defending Holy Terra when the time inevitably came. Vital equipment, especially the irreplaceable Terminator suits, was also being evacuated into orbit.
Each wave of Chaos was met with a storm of lasfire, as the 409th, along with several other Imperial Guard regiments, held the line around the Ultramarines' fortress-monastery. What remained of the Ultramarines chapter still on the ground aided in the defense as much as they could, but it was clear that they were running low on ammunition and that their numerous wounds were beginning to catch up to them. In the early stages of the Second Battle of Macragge, the Ultramarines had provided fearsome support for the Imperial Guard, and the planetary defenses had inflicted a dear toll upon the Chaos fleet. The forces of Chaos were relentless, throwing endless waves of poorly-armed cultists and lesser daemons with the sole purpose of soaking up the defenders' ammunition. When one wave was fought off, the next would charge before the Techmarines and Apothecaries could finish making their rounds.
As the heretical battlecries filled the air once more, the exhausted defenders of Macragge forced their bodies to move. Even an extra day for the evacuation effort could make all the difference. Even the most optimistic, however, found it hard to believe that they would last past the hour. All that could be seen for miles around was a solid mass of daemons and cultists, with the titanic forms of Traitor Astartes occasionally towering above the crowd. The blasphemous litanies chanted by the enemy stripped many of their sanity. The lucky ones received a lasbolt to the head from the person next to them.
The defenders slowly lost ground, as the forward trenches devolved into bayonet combat. Traitor Astartes would wade through the doomed positions, absorbing enormous amounts of punishment as the Guardsmen within desperately tried to hold them back. The enemy horde continued their charge through the trenches, overrunning positions with their sheer numbers. The bodies of the dead, carried forward by the momentum of those behind them, soaked up yet more weapons fire from the defenders.
The defenders slowly began to retreat within the thick stone walls of the fortress-monastery in hopes of buying even a few more hours for the Thunderhawks to make their rounds. In some areas, the bodies of the dead were piled so densely that they formed makeshift floors, and the sight of them lowered the defenders' morale even further. The sight of dead Astartes amongst the bodies caused some to break outright, reducing them to gibbering wrecks that their comrades killed out of mercy. It was already abundantly clear that Macragge was lost, and several Imperial Guard regiments had already begun to evacuate to orbit, torching their heavy equipment and anything else they couldn't take with them.
"Commissar! The right flank's been overrun! We're cut off!"
The commissar of the Valhallan 409th quickly glanced around the area, noticing that the unit to their right flank had indeed been overrun, allowing the enemy to encircle what remained of the unit. Earlier fighting had whittled down the 409th to barely a third of full strength, and the deaths of most of the senior command staff had left the commissar the commanding officer by virtue of seniority. To hope that they could fight their way through such a horde when faced with such odds was beyond naively optimistic. In all his years of service to the Emperor, he knew that his life would end in such a manner. He hefted his bolt pistol in one hand, and made sure his remaining magazines were in easy reach. He drew his chainsword, and raised it into the air.
"Then we go down fighting! Men of Valhalla and Catachan, stand with me one final time! Fix bayonets and charge!"
The remnants of the 409th surged forward, their bayonets drawn. They crashed into the enemy line, hacking and slashing in every direction. There was no need to aim: the enemy was packed so thickly that any bayonet thrust was guaranteed to hit something. As if the universe wanted to add insult to injury, the sacrifice of the 409th had not slowed down the forces of Chaos at all. The mass of daemons and heretics and traitors trampled over the Guardsmen of the 409th, continuing towards the gates of the fortress-monastery. Small explosions were seen where the 409th once stood, as the Guardsmen detonated their remaining grenades and even overcharged their lasrifles in a last-ditch attack on the enemy. Shrapnel peppered the enemies closest to the blasts, but the bodies of the dead were quickly trampled underfoot by the advancing mob.
The Imperial fleet in orbit was spearheaded by the Glorious, an old and irreplaceable Oberon-class battleship. The troopships at the center of Battle Fleet Ultima were busily unloading dropships, then sending them back down to the planet for another load of Imperial Guardsmen. The Ultramarines chapter fleet, lead by the might Battle Barge Caesar, was busily doing the same. Even from space, it was clear that the ground forces could not hold out long enough to evacuate much more of their number. They lasted long enough to see the two hundred and first day of the Second Battle of Macragge, when a message from the surface sealed the world's fate.
"Admiral, the situation is hopeless. The fortress-monastery is being overrun. The incoming wave of dropships shall be the final group. We are destroying the landing pads before they too are overrun."
The Admiral of Battle Fleet Ultima turned towards his bridge crew, issuing orders to leave orbit immediately. Before he could tell his astropath to relay the same orders to the rest of the fleet, a hand on his shoulder stopped him. He did not need to turn around to know it was the Inquisitor that was hitchhiking, for the lack of a better word, aboard the Glorious. He had simply strolled aboard the ship as they prepared to join up with the makeshift Battle Fleet Ultima, and ordered them to continue going wherever they were originally headed. He was almost never seen by the crew, which suited them just fine, except when one of them mentioned seeing a vessel with a malformed silver trident head painted on the side.
"Exterminatus."
The Admiral paled for a moment, before cancelling his previous orders. He contacted the gun decks, relaying that dreaded world throughout the crews. He turned to the astropath to relay the Exterminatus orders throughout the rest of the fleet. There was no time for the conventional combination of lances and Cyclonic Torpedoes. Atmospheric Incinerators, normally reserved for the most extreme circumstances, were fired. Macragge still burned when Battle Fleet Ultima retreated into the Warp.
Space Station Ikaruga, Somewhere in the Galaxy
Ten Days After the Second Battle of Macragge
Kallen Kozuki wasn't an awfully imposing woman. Standing at slightly more than 1.5 meters in height, she found herself craning her neck to look most people in the eye. Those that underestimated the head of the Black Knights' Military Arm-Special Forces Division never did so again. Known as the "Crimson Lotus," her custom Guren-Seraph blazed a path of destruction through the enemy forces. She was an incredibly potent Psyker, renowned for her ability to alter the flight paths of incoming weapons fire, often sending it back towards the enemy, and to see several seconds into the future, augmenting her formidable hand-to-hand skills.
The Intelligence Center of the Ikaruga was perhaps the single most technologically-sophisticated room aboard the vessel, where the latest computers constantly intercepted, translated, and sorted countless astropathic communications. It was also the most depressing, as almost anything worth attention was doubtlessly an Imperial communication listing staggering death tolls on some battlefront or another. Kallen was currently on her way there, the orderly on duty having informed her that something interesting had come up.
As Kallen rounded the corner, the guard on duty stood up and began to salute, before she waved him to sit back down. As he scanned over her identification with the sluggishness that came with being a first-timer to desk duty, she noticed that he was wearing the dark grey tunic of the Orbital Planetary Assault Wing, instead of the black-and-silver tunic of rank-and-file Black Knights soldiers. She puzzled over what a member of the elite OPAW was doing on desk duty, when his nametag came into view and it all clicked.
Reserve Sergeant Johann Nathan, formerly of the 5th OPAW, but was recently transferred to the 10th OPAW. Barely twenty-three, and he'd already seen more action than most Black Knights see in their entire careers. She'd personally commanded the campaign that was his first taste of combat: an assault against a Tyranid Hive Fleet four years ago in which a Lictor had taken off his arm. Almost as soon as his arm had been regenerated, he'd been tossed into the Third Necrotic War. For somebody who had never seen Necrons before, he did surprisingly well until the Battle of Deneb. The poor kid started talking again after about a week, and he sat out the rest of the war in a reserve unit.
Apparently satisfied that she was indeed General Kallen Kozuki, the Reserve Sergeant waved her through, helpfully placing his hand on the biometric sensor and opening the armored door for her. Stepping inside, she instantly noticed that the air was a few degrees cooler than the air outside. A few millennia ago, it would have been to cool down the computers. Now, it was done out of sheer force of habit. She was hardly surprised to see a young-looking woman with waist-length green hair already there. Even after all these millennia, Kallen could never get over the feeling that CC's eyes were always looking directly into her soul. Then again, she was a Psyker of even greater power than Kallen was, so such would not be a bad assumption.
"The latest dispatches intercepted from Imperial astropaths. They called down Exterminatus on Macragge. At least twelve Imperial Guard regiments, the entire Macragge PDF, and half the Ultramarines chapter were still on the ground when it occurred," the immortal summarized in her usual deadpan voice, as if the millions of lives snuffed out were as significant as insects.
Kallen tapped her earpiece twice, bringing up a private channel. Macragge was the final Imperial stronghold outside of Segmentum Solar. It was now time to act.
Suzaku awoke to the annoying beeping sound of his communicator. He fumbled it into his ear, knowing full well that only a few people aboard the Ikaruga knew of the private channel, and they never used it unless it was an extreme emergency. The last time it was used was just before the Third Necrotic War.
"General Kururugi speaking."
"Suzaku? It's Kallen. Wake Nunnally. Tell her that Macragge's fallen."
Before he could reply, CC's voice appeared on the channel, "And don't try to deny it. It's an open secret where the governor can be found after-hours. You might as well move her nameplate to your door and be done with it."
Suzaku could practically feel the green-haired witch's smirk. He closed the channel, and turned the sleeping figure beside him, shaking her gently.
"Nunnally. Nunnally…"
Nunnally blearily opened her eyes, as if to reply. She began to close them again, before they shot wide open.
"WHAT! Macragge's fallen?" she exclaimed, shooting up at a speed that surprised even Suzaku.
No, thought Suzaku as he cracked his nose back into place, I was not just surprised by Nunnally. It was simply not energy-effective to move out of her way.
Nunnally quickly pulled a robe on, tying the sash around her waist as she inserted her own communicator into her ear. Tapping in the various governmental channels, she began to call the upper echelons of the Black Knights civil government, calling an emergency session in fifteen minutes. She could see Suzaku off to the side, presumably doing the same with his chiefs of staff.
Reserve Sergeant Johann Nathan was already at his desk when a slight pressure in his skull told him that the Ikaruga had engaged its Warp drive. Before he could wonder why, the news was broadcast over the Ikaruga's PA system. The Ikaruga was moving out, and the Black Knights were now on a war footing. All reserve units were to be immediately upgraded to alert status. Quite a few OPAW members groaned at that, as alert status meant sleeping in the drop bays wearing full body armor. Silence reigned when Governor Nunnally announced their destination: Terra.
