The battlefield was shrouded in murky green mist and lashed by merciless, poisonous rain.
Mortarion towered over his brother Roboute Guilliman, broader and more massive in build.
The corroded, ever-oozing Barbarus plate that sheathed him was nothing less than a mobile fortress of disease.
Behind him, a pair of tattered moth-like wings were spread wide, casting eerie shadows and churning the foul-smelling air.
"Mortarion, the time has come to end this long and pathetic feud between us."
Guilliman stared fixedly at his brother, eyes burning with anger.
Both his hands gripped the hilt of the Emperor's Sword. Golden flames roared along the blade, driving back the toxic fog and the chill, forming a zone of sanctified clarity around him.
"Failure will be your end, Guilliman," Mortarion looked down on him.
"From the moment you set foot on this battlefield, which I have so painstakingly prepared, your defeat was already inevitable.
Kneel and beg for mercy, and I may be gracious enough to spare your life."
"Did Typhus becoming the lord of your Legion drive you insane, or has Nurgle's soup filled your skull, blinding you and robbing you of coherent thought?"
Perhaps Guilliman's long time spent in an unknown dimension had left its mark on his tongue; every word was viciously barbed.
Each sentence struck at Mortarion's sorest points, driving him to the brink of fury.
"I am the true and only commander of the Death Guard Legion!"
Mortarion's voice suddenly rose in rage.
The poisonous mists around him churned and howled in response to his emotions.
"You might want to ask Typhus whether he agrees," Guilliman shrugged.
"Enough. This pointless bickering ends here.
Mortarion, you've lost. My fleet can annihilate you and your minions at any time. Kneel now, and I will see you granted a fair trial."
Mortarion laughed.
"You know nothing of my strength and cunning, brother. The real battle has only just begun."
Clang! Clang! Clang! Clang! Clang! Clang! Clang! Clang!
Over the din of explosions and battle cries, a dull, drum-like pounding rang out from deep within the dense fog blanketing the field.
Moments later, the mists were violently churned and pushed aside.
Bone-and-wood wheeled war-engines were being slowly heaved forward by hordes of twisted, mutant slaves.
These were Nurgle's Wither-Towers—siege engines reminiscent of the crude assault towers of primitive civilizations.
Their main structures were built from raw, unhewn logs whose bark and gnarled branches still clung to them.
Their surfaces were sheathed in thick brass plating, from which viscous slime dripped constantly. That brass, in turn, was carpeted in greasy green corrosion and blooming fungal growths.
Atop each Wither-Tower, a crude nozzle jutted out, like a primitive musket scaled up to monstrous size. Inlays of corrosive green gemstones glowed balefully along its length.
"Fire! Pulverize the Emperor's toys!"
The Chaos commanders barked their orders.
In the next instant, green lances of light speared out from the towers' emeralds, sweeping across the advancing Imperial Titans and armored columns.
At the same time, the crude nozzles swelled grotesquely and vomited torrents of tar-thick toxic sludge, which fell upon the Imperial front lines in a reeking, yellow-smoked deluge.
The sludge splattered across vehicle armor with a hideous hissing.
Stout metal plates frothing and softening almost at once, then finally catching fire.
Green vapor billowed upward, carrying potent toxins and corrosive agents that spread yet another veil over the battlefield.
A Warhound-class Titan, unlucky enough to be caught full-on by one of these streams, took the brunt of the attack.
The entire mass of liquid burst against its hull, sending a tidal wave of super-acid crashing down its frontal armor, shredding the banners at its waist.
Cable insulation blistered and cracked away. Hydraulic lines split and burst. The acid ate into bare metal almost as swiftly as it devoured softer parts.
The armor plates of a Reaver-class Titan corroded into spongy, dangling slabs, sagging and sloughing off its frame.
And this was only the beginning of the nightmare.
Amid tolling bells, a second wave of Chaos reinforcements appeared—far more terrifying in scale.
At their forefront surged Nurgle's own hordes, advancing like a rolling green tide.
They squeaked and chittered, their bodies slick with slime, their numbers beyond counting.
Behind them strode tall, imposing Plaguebearer heralds, swinging great incense censers as they tried to marshal and direct the chaotic swarm of lesser daemons.
Suddenly, the sky darkened.
A vast cloud of filthy flies descended upon the field, so dense they blotted out the light.
The buzzing of countless wings merged into a maddening drone that hammered at the mind.
The ground shook as beasts, grown from heaps of stitched-together carcasses of all kinds of creatures, came thundering out of the mist, roaring.
Like living mountains of flesh, the Greater Unclean Ones lumbered forward among the daemon ranks—slow, but utterly inexorable, their every footfall making the earth groan.
And that was not all.
Woo! Woo! Woo!
Khorne's piercing, blood-mad warhorns blared, their sharp notes cutting through the clash of warhammers and chainswords.
An army of berserk knights, clad in blood-red heavy plate and mounted on daemonic steeds armored in bone plates and spikes, launched a furious charge toward the Imperial flank—like a crimson storm crashing in from the horizon!
On the opposite side, the foul air suddenly grew sweet and intoxicating—yet so cloying it turned the stomach.
The mists flushed pink and purplish red.
Slaanesh's daemonettes and Heartseekers slid out from the cracks between shadow and sensation, accompanied by eerie laughter and susurrant whispers.
Their forms were elusive, their beauty inhuman and lethal—perfect snares aimed at the weakest points in a warrior's resolve.
Gigantic daemon engines, belching hellfire, rolled into the fray as well, bolstering the Chaos Titan legions in their assault on the Imperials.
The arrival of this tide of monstrosities upended the battle.
The advantage the Imperium had carved out through rivers of blood was washed away by the endless waves of warp-spat daemons.
Guilliman's expression hardened.
The situation had exceeded even his worst predictions.
He had anticipated Mortarion's trap. He had expected Nurgle's reinforcements.
But that Khorne and Slaanesh would send their servants at the same time—this he had never foreseen.
This meant that the Ruinous Powers had, for once, set aside their feuds and united against the Imperium.
…
At that moment, a barefoot girl in a pure white dress stepped onto the battlefield.
Battle Sisters, led by Canoness Yolande, formed a protective ring around her, chanting hymns in praise of the Emperor.
They scoured the onrushing lesser daemons with boltguns and flamers, purging them in holy fire.
The girl walked forward, step by measured step—and a miracle followed her.
Wherever she passed, the air rippled like water struck by a thrown stone.
Golden waves seemed to spread outward through space itself.
Moments later, within that warped shimmer of light and shadow, a blurred host of warriors wreathed in flame abruptly took form.
The Emperor's Cursed Legion had descended onto the field.
The eyes of those fallen heroes burned with endless hatred for Chaos.
They moved in flawless coordination, unleashing precise and merciless volleys into the oncoming daemon tide.
Their bullets trailed fire and were lethally effective against daemons: wherever they advanced, daemons died in droves.
If the number of daemons was truly infinite, then for every host destroyed, still more would come snarling out of the warp.
"So, Father has been dragged into this battle as well, it seems."
Even at the sight of the Cursed Legion, Mortarion showed no sign of alarm. Instead, he gave a low, grating laugh.
"Unfortunately, not even he can alter the inevitable. Just as on Terra, he could save nothing in the end."
"This universe is not some plaything where the gods alone dwell amid chaos," Guilliman sneered at his traitor brother's words.
"Humanity will win this war."
"Was it that Nameless fellow who filled you with such courage?" Mortarion mocked.
"Do you truly believe that strange, originless man, with his inexplicable behavior, can stand alone against all four Chaos Gods?
Cast off such idiotic fantasies, Roboute.
If you had ever truly felt the supreme power of the Ruinous Powers, you would never utter such childish nonsense.
He may be a nuisance—but he is far from invincible."
"The same can be said of you," Guilliman shot back.
"If you had witnessed the power of the Nameless Ones for yourself, you would know there is a God in this universe.
This God is neither the Emperor nor any primordial deity, but a Nameless Existence before whom all the laws of the cosmos must bow."
"Ignorance breeds arrogance, Roboute. But so be it. Allow me to enlighten you," Mortarion said.
Guilliman wasted no more breath.
Words would not free humanity from suffering.
The Primarch charged his traitor brother.
The servos of the Armour of Fate whined in a deep hum as they drove themselves at full power.
He became an afterimage of golden fire as he launched his first strike.
The Emperor's Sword cleaved the air, imbued with the will to scour all evil, lunging straight for Mortarion.
Mortarion moved as well, bringing his colossal scythe down with speed that belied its size.
Guilliman neither dodged nor tried to evade. He roared and swung the Emperor's Sword with all his might, choosing the most direct, head-on clash!
Claaang!!!
The two weapons, each laden with its own symbolic meaning, slammed together.
The detonation was louder than thunder, and a terrible shockwave blossomed outward in a sphere.
Within a hundred meters, rubble, corpses—even small daemons—were hurled aside and swept away.
Holy golden flame met foul, dark-green toxic fumes, hissing as they devoured each other and vanished.
At the very heart of the clash, the air writhed with astonishing visual distortions—two wholly different powers colliding head-on.
The duel between the two Primarchs escalated rapidly. Each impact made the very ground quiver.
Guilliman's skill was extraordinary, his footwork swift and sure. The flames of the Emperor's Sword bolstered his resistance against Mortarion's Nurgle-blessed corruption.
Mortarion, in turn, leaned on his overwhelming physical strength, vast attack range, and armor that negated conventional injury to steadily press the attack.
Both sides were intent on killing the other, holding nothing back.
Then, suddenly, something unexpected happened.
The shadow behind Guilliman twisted as if it were alive.
A tall, slender figure emerged—clad in a purple-tinged blue robe, with the head of a bird and cunning eyes gleaming with malice.
The ever-changing Lord of Sorcery: Amon Chakai.
He had cloaked himself in Tzeentchian sorcery right at the Primarch's side, waiting for the perfect moment to strike.
Guilliman was caught off guard.
He should have realized it: with Khorne and Slaanesh both committed to the battle, there was no way Tzeentch would abstain.
The bird-headed sorcerer's true purpose lay here.
Nine eerie Tzeentchian sorcerers appeared alongside Amon Chakai.
They formed a strange formation, raising staves and tentacles as they chanted ancient and obscure incantations, riddled with paradox and logical traps.
"Bind the body immutable upon the ever-changing path!" Amon Chakai cried.
Guilliman felt his limbs suddenly seize up.
Multiple magical chains, their colors constantly shifting, sprang from nothing and coiled themselves around his wrists and ankles.
He roared and shattered several of the chains.
But to a warrior of Mortarion's caliber, the time this bought was more than enough.
The Daemon Primarch swung his massive scythe at a perfect angle, its blade smashing into the spine of the Emperor's Sword.
Clang!
A tremendous force rang up the blade. Guilliman's wrist spasmed.
The Emperor's Sword, blazing with golden light, was torn from his grasp, spinning away to plunge into the ground more than ten meters distant.
Alarm bells screamed in Guilliman's mind. He was just about to break off when Mortarion's follow-up attack came crashing in.
Raising a howling gale, the scythe arced down toward his neck. Guilliman ducked low to avoid it.
Mortarion seized the opening and lunged forward.
His power-armored knee, heavy as a battering ram, snapped up and smashed into the front of Guilliman's helmet.
Bang!!!!!
A chest-rattling, dull impact.
Even with the cushioning field of the Iron Halo and the protection of the helmet, the knee strike still inflicted massive damage.
The helmet's front caved in and shattered, bursting apart.
Guilliman's stern features were suddenly exposed to the toxic air.
A tiny, razor-edged shard of helm grazed his cheek, scoring a shallow cut.
The wound closed almost at once, yet a single bead of blood welled up and rolled down his face.
That droplet never soaked into the soil. The instant it touched the ground, it vanished.
"Heh-heh-heh!!"
Ku'gath, hidden in the fog, chuckled to himself. He had done it—he had acquired the blood of a Primarch.
The dazed Guilliman unleashed the power of the Hand of Dominion.
As Mortarion tried to close in, a storm of bullets raked his position, forcing the Daemon Primarch back with a roar of pain.
Guilliman rolled, sprang for the Emperor's Sword, and had just regrouped to launch another charge when—
In the distance, a crumbling tower of piled skulls spewed strands of viscous, almost tangible green energy into the air.
The first beam coiled itself around Guilliman's right wrist—the hand clenching his sword.
The second lashed tight about his throat.
The third wrapped his waist and abdomen in a crushing bind.
Then a fourth, a fifth…
From all directions, green beams streaked in, lashing around him and anchoring him in place.
They not only restricted his movements, but steadily leached the strength from his armor and his body alike.
Guilliman strained against them, muscles bulging, the servos of his power armor overloading and grinding with a tortured whine.
The golden flames of the Emperor's Sword scorched relentlessly at the light-ropes, searing through them with angry hisses and snapping several.
But there were simply too many bindings.
For the moment, Guilliman was locked to the spot, unable to break free!
Seeing this, Tribunus Carken, who was fighting nearby, cried out in panic:
"To the Primarch! Move, now!"
"All units! To the Primarch at any cost—move!"
"Protect the Primarch!" Sicarius shouted to the Honour Guard after cutting down a daemon that blocked his path.
Around them, Imperial troops abandoned their current foes, flinging themselves heedlessly into the fray, charging toward the spot where Guilliman was held fast.
They hacked a bloody path through the daemon sea, desperate to reach him.
But the daemons, sensing their intent, threw themselves into their way with equal ferocity, and a brutal melee erupted between the two forces.
…
Meanwhile—
Empowered by Crimson Mechagodzilla, Datch had just obliterated a Warlord-class Titan that had been targeting him, felling it with a single Crimson Beam.
He rescued Caleb Dunkel, captain of a Warhound-class Titan, and his crew, then helped them repair their Titan, which had been savaged by the Wither-Towers.
Perched on his shoulder, the creature Puhg continuously radiated life force to counteract Nurgle's rot, restoring many rusted Titans and vehicles to working order.
The Masque of Slaanesh, the Changeling, Skarbrand, and the Zarhulash all fought on the side of the Imperials.
They hunted daemons without mercy, carving out fresh breathing room for Imperial forces.
Naturally, these actions enraged the Chaos creatures.
"Traitors! Shame on you before the Supreme Gods!" they screamed over and over.
With Datch's help, the Imperial Titan Legions and armored formations managed not to be overrun by the daemon hosts and traitors.
Instead, the front stabilized into a bitter stalemate.
"And that's another one down!"
In his Mechagodzilla form, Datch fired a Crimson Lotus Beam, obliterating a Wither-Tower that had been spewing poison gas toward the Imperial lines.
The tower's remains scattered across the ground and went up in roaring flames.
Just as Datch was seeking his next target, a new red icon suddenly flashed to life on his minimap.
He opened the notification—and was left momentarily speechless.
The important NPC Roboute Guilliman was on the verge of death.
If Guilliman died, the development of his Imperium route would be cut short, and Datch would lose a chunk of points.
After all, he was part of the Imperial faction; the death of a key NPC counted as their failure.
These were penalty rules the devs had put in place for Story-Mode players, to guarantee a good gameplay experience and smooth narrative progression.
After all, there were always players willing to slaughter an entire village over a single chicken, derailing half a quest line in the process.
Ah! Ah! Ah!
Brother, please don't die on me so early.
If you die, what happens to my final score?
Datch howled inwardly. Without another moment's hesitation, he triggered a slide and blinked to the quest NPC's rescue.
In the next instant, Crimson Mechagodzilla appeared in the sky above Guilliman.
With a roar like Mount Tai collapsing, he crashed down—smashing straight into the rotting tower that had been spewing those clinging green beams to bind Guilliman and the daemons swarming below.
The earth shook with a cataclysmic crash, as if a meteorite had struck.
Even as he landed, Datch, still in his Mechagodzilla form, loosed an ear-splitting roar.
Rooooaaaarrrrr!!!
Before the echo faded, a blazing crimson ray burst from his maw.
A colossal spiral beam of golden-tinged red swept across the battlefield, centered on Mechagodzilla.
Towering, festering structures were sliced clean in half one after another, dissolving into molten, blazing wreckage that vanished amid deafening explosions.
Freed from all bindings, Guilliman regained his mobility. A faint smile touched his lips.
"I knew the Nameless One was watching over me. He would never abandon me."
Mortarion's face twisted.
He had been so close to finishing Guilliman—only for this stranger to ruin everything.
"Prepare to die!" Guilliman gripped the Emperor's Sword and leapt high into the air, vowing to slay his treacherous brother as he brought the blade down on Mortarion.
Mortarion swept up his great scythe to parry, and the two clashed once more.