"Emperor preserve us," whispered Moderati Cassar, completely unable to hide his horror and no longer caring who on the bridge heard him.
The thick miasma of gross, decaying gases still hung heavily in the air all around the Titan. He could only dimly see the trenches below, along with the bone-white warriors of the Death Guard slowly emerging from their deep bunkers.
Shortly after the urgent order to seal the Titan had been given, the Death Guard had similarly pulled back into hard cover, clearly in receipt of the exact same survival coordinates as the Dies Irae.
The Isstvanians had received no such mercy. The sudden, calculated withdrawal of the Death Guard had drawn the unsuspecting rebel soldiers forward into the open, forcing them to bear the full, devastating brunt of the bio-weapon.
Masses of thick, mucus-like flesh now choked the narrow trenches. Half-formed human corpses loomed from the mire, their faces completely melted, and their rot-bloated bodies split wide open. Thousands upon thousands of Isstvanian citizens lay in horrific, decaying heaps, while thick streams of rotting fluids ran the entire length of the fortifications like a foul river.
Beyond the immediate battlefield, total death had consumed the vast forests that lay just outside the Choral City's limits. The once-lush woods now resembled endless, silent graveyards of blackened trunks. The very earth beneath was completely saturated with biological death, and the atmosphere was thick with a suffocating blanket of foul gases released by the vast oceans of decaying biological matter.
"Report," said Princeps Turnet, stepping back into the cockpit.
"We're fully sealed," said Moderati Aruken from the opposite side of the bridge. "The crew is fine, and my instruments are showing a zero reading of internal contaminants."
"The virus has successfully burned itself out," Turnet noted.
"Cassar, what is left out there?"
Cassar took a heavy moment to gather his thoughts, still violently struggling with the hideous, unbelievable magnitude of the mass destruction. He could never have even imagined a nightmare this vast had he not witnessed it firsthand through the electronic eyes of the Dies Irae.
"The Isstvanians are… completely gone," he said softly, his voice trembling.
He peered through the swirling green clouds of gas at the massive silhouette of the city standing to one side of the Titan. It was hard to tell what was what, but he could see the blackish-green-coloured waste that had almost filled the trenches.
"All of them."
"And the Death Guard?"
Cassar looked closer through his targeting optics, seeing no signs of that bone-white armour buried in the gory, liquid chokepoints. He tried marking exactly where several Astartes had been caught in the open, but it was nearly impossible, since there was nothing to be seen.
Down in the inner trenches, Alexei's mind was already working silently beneath that fog, his necromantic virus systematically infecting those almost-empty, fluid-filled suits, taking control of their bodies, standing them back up, preparing them to be turned into an unyielding vanguard, while simultaneously hiding from the scanners of the Dies Irae.
He had been working nonstop and was still going. He had but a few minutes to finish what he was doing before the final shit-fire-storm hit the fan.
"I can't tell for sure, my Princeps, maybe some of them were caught out there," Cassar reported, entirely unaware of the silent resurrection occurring in the mud. "From previous scans, it looks like a lot of them are dead, but the warning must have gotten to most of them in time."
"The order?"
"Yes, princeps. The order to take immediate cover."
Turnet peered out through the Titan's main viewing eye on Aruken's side of the bridge. Through the greenish fog, he tried to spy the potential surviving Death Guard and other Astartes warriors cautiously securing the trenches around their bunkers, their heavy boots treading right through the foul, liquefied remains of the Isstvanians... but he was unlucky.
"Damn," Turnet muttered under his breath, his fist tightening.
"We are truly blessed," Cassar said, his voice filled with awe. "They could so easily have been--"
"Watch your mouth, Moderati!" Turnet shouted angrily, spinning around to face him. "That religious filth is an absolute crime by the direct order of--"
Turnet's voice cut off instantly as a sudden, violent movement caught his eye.
Cassar followed the princeps' stunned gaze just in time.
"Throne..."
.
Horus stood before the assembled group of remembrancers. They were a group of poets, journalists, imagists, and writers sent to accompany the Imperial forces during the later years of the Great Crusade, once the Emperor had returned to Terra.
And the Warmaster was going to make use of them. Or some of them, at least. It was his official declaration, one that would and should be remembered for millennia to come.
"You see now... This is war. This is cruelty and death. This is what we do for you, and yet you turn your face from it."
His voice wasn't loud per se, but it was powerful, filled with his conviction and the authority of a demigod-Primarch.
Weeping men and women clung tightly to one another as they were forced to watch the flesh-eater virus tear through all of Isstvan II... the sight of such a monstrous genocide. They were completely unable to understand the terrifying scale of the slaughter that had just been carried out in the name of the Imperium.
"You have come to my ship to chronicle the Great Crusade, and there is much to be said for what you have achieved, but things change and times move on," Horus continued.
As he spoke, the elite Space Marine warriors stationed along the sides of the audience chamber quietly closed the massive heavy doors. They stood firmly in front of the exits, holding their bolters tightly across their chests, ready for what was to come.
"The Great Crusade is over," Horus said, his voice booming with immense power and cutting authority.
"The ideals it once stood for are dead, and all we have fought for has been a lie. Until now. Now I will bring the Crusade back to its rightful path and rescue the galaxy from its abandonment at the hands of the Emperor."
Astonished gasps and panicked wails instantly spread through the crowded chamber at Horus's words. What he was saying was treason; it was the highest form of treason, and for some among them, it was even more...
The Warmaster deeply relished the sudden freedom he felt in finally saying these things out loud. The exhausting need for absolute secrecy and misdirection was now finally completely over. Now, he could finally unveil the true grandeur of his designs for the galaxy, casting aside his false facade of loyalty to reveal his ultimate purpose.
The preparations had been done for the first phase of his plans, and he used this moment to reveal his plans to these worms, who were worth less than anything he could imagine.
"You cry out, but mere mortals cannot hope to comprehend the scale of my plans," Horus said, thoroughly savouring the looks of pure panic that began to spread across the faces of his audience.
No political orator or iterator could ever have held a crowd so completely in the palm of his hand. It was what made Horus so dangerous as he was, and why his betrayal will continue to have such galaxy-spanning, terrible consequences.
His charisma was off the charts. Almost everyone liked him, no, loved him. The Emperor loved Horus the most among all his sons. It was that charisma that allowed Horus to turn several of his brothers to his side already, and create a treasonous force that was no weaker than the loyalists were... although that was if you ignored the Ultramarines, the largest Legion. Still, he had prepared for them not to attend what was to come.
"Unfortunately, this means that there is no place for the likes of you in this new crusade," Horus noted, his expression turning cold. "I am about to embark on the greatest war ever unleashed on the galaxy, and I cannot be swayed from my course by those who harbour disloyalty."
Horus smiled. It was the chilling smile of a once angelic executioner. Everyone knew what was coming as they saw his bloody, charming, and sinister smile.
"Kill them," he said flatly. "All of them."
At the Warmaster's direct order, a devastating wall of bolter fire penetrated the trapped crowd. Human flesh burst in wet explosions, and a hundred bodies dropped quickly to the floor in the very first barrage.
Terrified screaming erupted as the desperate crowd tried to get away from the armoured Astartes marching into their midst. But there was absolutely no escape. Guns blazed continuously, and roaring chainswords rose and fell in bloody arcs.
The complete slaughter took less than a minute. Horus turned his back on the fresh pile of bodies to watch the final death throes of Isstvan III from the grand viewing ports.
Abaddon, First Captain of the Sons of Horus Legion, emerged from the shadows where he and Maloghurst, Horus' Equerry, had silently watched the execution of the civilian historians and artists.
"My lord," Abaddon said, bowing low before his Primarch.
"What is it, my son?"
"Ship surveyors report that the virus has mostly burned out."
"And the gaseous levels?"
"Off the scale, my lord," Abaddon smiled darkly. "The gunners await your orders."
Horus watched the swirling, noxious green clouds of the Life-Eater completely enveloping the dead planet below. All it would take to finish the job was a single spark.
He envisioned the ruined world as the frayed end of a massive fuse. This fuse would soon ignite the entire galaxy in a searing conflagration of civil war, leading to an inevitable, bloody conclusion on the steps of Terra itself, when he held his father's heart in his hands and looked down on him...
"Order the guns to fire," Horus said, his voice dropping into a register of cold, absolute finality.
"Let the galaxy burn!"
.
All it took was a single spark.
An entire planet's worth of decaying matter turned the atmosphere of Isstvan III into a thick, suffocating cloak of highly combustible green gases.
The blinding lance strike from the Horus' Flagship, the Vengeful Spirit, punched through the upper atmosphere, straight into the sickly miasma. Its beam instantly ignited the gas with a dull and hollow whoosh that violently sucked the remaining oxygen right out of the air.
Boom---WHOOOOOOOOOOOOOOOOOOOSHHHHHHHHHHH---!!!
In a single second, the air caught fire, ripping across the landscape in a howling maelstrom of blinding white heat and deafening noise. Entire continents were instantly burnt to a crisp, their landscapes charred down to nothing but scorched rock and magma. The vast oceans of decaying humans were completely vaporised in mere seconds as supersonic firestorms swept across the planet's surface.
Large and previously prosperous cities violently exploded from within as underground gas lines ruptured and detonated, throwing blazing towers of fire into the sky. Nothing caught out in the open could hope to survive.
Flesh, stone, and heavy metal were either turned into black glass or melted and evaporated under the unimaginable temperatures which were brought to bear. Entire complexes of factory buildings collapsed into rubble, the liquefied bodies of their former occupants instantly reduced to ash on the wind.
A storm of destruction swept relentlessly around Isstvan III. It looked as though the entire globe had been turned into a star.
Those Space Marines who had survived the initial viral attack but had failed to reach deep enough cover found themselves facing roaring flames that seemed to reach into every small crack and hiding spot, instantly consuming them.
By the time the massive energy recoil faded on the Warmaster's flagship in orbit, 8 billion people had died on Isstvan III.
...
Down within the inner western trench lines, right at the epicentre of the Death Guard's fallback sector, Alexei stood completely still in the open when the lance strike happened.
The sky above him was already turning into a roaring sheet of cascading plasma. The supersonic shockwave of heat was igniting the green gases and rolling toward his trench at terminal velocity, threatening to melt the very ceramite off his bones and those of the hundreds of Space Marines he had saved.
Inside him, the Meta Essence operated at a hyper-frequency.
He knew that even with Mortarion's supreme durability, which he had enhanced using another virus, the sheer, ungodly temperatures of a planet-wide firestorm would reduce his and his brother's current physical bodies and armour to molten slag before they could understand what happened.
He needed a shield, and he needed it instantly.
Thankfully, he had prepared for this over the last couple of hours as he had rushed to save as many of his brothers and cousins as possible. He had spread his own virus and collected what remained of them right there, where they stood at the moment.
No one would open a bunker at this stage, and there was no time to look for another one.
'Deploy', he thought.
From every single armour vent, joint gasket, and exhaust port of his bone-white plate, an immense, pressurised torrent of a brilliant, glowing blue gas erupted into the air.
It wasn't normal air; it was a highly specialised, hyper-dense viral mist engineered specifically to consume heat, neutralise methane, and absorb thermal kinetic energy. And what's more, it worked immensely well with the anti-flesh-eater virus he had created to save his brothers.
But not only from him, from all those poor Death Guard and World Eaters, he couldn't save in time, who had died before the virus could fully heal them, all those whom he had brought back using his necromantic virus, also started releasing this particular brand.
The blue gas spread with terrifying speed, rapidly forming a massive, dome-like fog bubble that completely encapsulated Alexei, his reanimated undead vanguard, and the surviving loyalists with him.
A fraction of a second later, the global firestorm slammed into the western front.
The wall of blinding white fire crashed against the blue fog with a cataclysmic sound. Outside the bubble, the trenches turned to vapour and ash and the remaining Isstvanian dead were instantly deleted.
But inside the thick, swirling blue gas bubble, the temperature remained relatively stable. The specialised virus in the air greedily stored the massive heat, replicating exponentially as it absorbed the thermal radiation, creating a layer of biological insulation.
The planet was burning, the galaxy was officially on fire, but in the dark heart of it all, Alexei and those who stood with him had just survived the end of the world.