When the second wave of "reinforcements"—the Iron Warriors, Night Lords, Word Bearers, and Alpha Legion—tore off their disguises and turned their weapons toward the backs of Ferrus, Vulkan, and Corax, the nature of the battle shifted from "war" to "execution."
The encirclement was rapidly tightening.
At the eye of the storm on the battlefield, the Iron Hands Primarch Ferrus Manus had descended into total madness.
If the other Primarchs were fighting, then Ferrus was burning.
His rage was so scorching that the surrounding air was distorting.
With every swing of his Warhammer, "Forgebreaker," it brought a teeth-grinding sound of shattering bone and exploding metal.
Even though surrounded, even with his "brother" Perturabo directing artillery fire into his flank, Ferrus had eyes for only one person.
That figure clad in ornate purple Power Armor, wielding a silver daemon sword—Fulgrim.
"Traitor! Look at me!!"
Ferrus roared, his voice sounding like two rusted iron plates grinding against each other, filled with the agony of betrayal and the resolve to kill.
He smashed through a Phoenix Guard Terminator who tried to block him, charging before Fulgrim like an out-of-control heavy tank.
This was the final exchange of glances between the once-closest of brothers before the end of their fates.
A poignantly beautiful yet twisted smile hung on Fulgrim's face; the "Blade of Laer" in his hand shimmered with an eerie purple light, as if thirsting for the nourishment of blood.
"You were always so ill-tempered, Ferrus."
The Phoenix's voice was soft, yet more lethal than a viper's fangs.
"This is why you cannot see the truth. You are too obsessed with iron, yet you ignore the pleasures of the soul."
"Soul? You disgusting monster!"
Ferrus's response was a heavy, powerful sweep.
"Forgebreaker" came crashing down with the force of a thousand thunderclaps; Fulgrim dodged elegantly to the side, but Ferrus's assault was like an unrelenting tsunami.
"Is this all you've got? Traitor!"
Ferrus roared, a hammer blow knocking aside Fulgrim's defense, followed by a punch to his brother's breastplate that sent The Phoenix staggering back.
"Stand up! Face your judgment!"
Fulgrim rose from the ground, a flicker of struggle passing through his eyes.
The silver daemon sword vibrated wildly, as if craving something.
The duel continued.
But as the daemon within the sword suddenly acted, an evil, ancient, and powerful force abruptly took over Fulgrim's body.
Caught off guard, Ferrus was struck down.
Fulgrim looked down at his defeated opponent, seeing his own reflection mirrored in Ferrus's eyes.
For a moment that seemed to stretch infinitely, he saw what he had done; in that eternal second, he understood he had made a terrible mistake.
But the blade fell in the next instant, the edge severing Ferrus's skin, muscle, and bone.
Blood and immense energy erupted from the wound.
A head rolled onto the black sands.
It was the head of The Gorgon.
Fulgrim was knocked down by the Impact; he stood up again, looking at the headless corpse before him.
"What have I done?"
Fulgrim took a trembling breath and wailed,
"By the Throne, what have I done?"
The Primarch had fallen.
With Ferrus's fall, the Iron Hands' battle line collapsed instantly.
The sons who had lost their father let out heart-wrenching wails.
No longer caring for tactics, they charged like madmen toward the Emperor's Children's positions, wanting only to reclaim their Primarch's body, only to be ruthlessly slaughtered to the last.
And on the battlefield's right flank, the situation for the Raven Guard was equally desperate.
On the other side of the battlefield, Corax witnessed this scene with his own eyes.
A bone-chilling cold pierced the heart of the Lord of Shadows.
Corax knew the day was lost.
If they did not retreat immediately, the Raven Guard and the Salamanders would follow suit.
"Retreat! Everyone, break through toward the thunderhawk landing zone!"
Corax roared into the vox-channel, while swinging his pair of Lightning Claws, shredding three Word Bearers into pieces.
But it was not easy.
Countless traitors surged forward like a tide.
Especially the Word Bearers; those fanatics seemed oblivious to pain, even attempting to bite the Raven Guard's armor with their teeth after their limbs were severed.
Corax carved a bloody path through the chaos, even reaching the Word Bearers' Primarch, Lorgar, at one point.
That charlatan, once considered the weakest Primarch, was now brandishing a Power Mace and chanting blasphemous scriptures.
"You betrayed us! Lorgar!"
Corax was beyond furious; his Lightning Claws tore through Lorgar's psychic shield, beating the golden Primarch into a state where he could not fight back.
Just as Corax prepared to deliver the fatal blow to Lorgar, a pitch-black shadow blocked him.
It was a fear colder than Death.
Konrad Curze, the Night Lord.
This pale, corpse-like Primarch stood before Lorgar, staring intently at Corax with black eyes that shimmered with madness.
"Run, Little Raven."
Konrad Curze let out a neurotic, cackling laugh, his voice as grating as nails on glass.
"Fly back into the shadows with your pathetic little birds. For today, the sky and the earth belong to us."
Two Primarchs who both commanded shadow and fear collided.
Konrad Curze's madness and cruelty made it difficult for the exhausted Corax, who was also worried about his sons' safety, to hold his ground.
Seeing his sons constantly falling around him and the encirclement closing in like a meat grinder, Corax gritted his teeth.
He knew he could no longer stay entangled.
Corax led the small remaining portion of the Raven Guard, like a flock of startled, lonely ghosts, desperately charging into the intricate wilderness and canyons at the edge of the Urgall Depression.
They escaped, but the Nineteenth Legion existed in name only; their glory and their numbers were left behind in this land of Death.
Finally, there were the Salamanders on the left flank.
Vulkan and his Eighteenth Legion were the hardest rock on the battlefield and the most resilient anvil.
Even when surrounded, even after witnessing Ferrus's Death, and even after Corax had been forced to retreat, they still did not break.
The Salamander warriors formed a massive iron circle, using their bodies and shields to construct a line of fire, steadfastly guarding one another.
"For Ferrus! For the Emperor! Salamanders, fight to the Death and never retreat!"
Vulkan swung his massive Warhammer.
He was like a burning mountain standing at the center of the battlefield, becoming the final spiritual pillar for all the loyalist faction.
As long as Vulkan had not fallen, hope was not yet completely extinguished.
However, among their enemies was a cold calculator—Perturabo.
From a command vehicle on the distant heights, the Lord of the Iron Warriors watched that tough nut through an Auspex.
He looked at Vulkan's seemingly infinite stamina and the Salamanders' impenetrable formation, a mocking curve touching the corner of his mouth.
For Perturabo, war was not a glorious duel but an arithmetic problem of efficiency.
Since melee was inefficient, he would change the method.
"That is Vulkan," an adjutant reminded him softly from the side.
"A Primarch is very hard to kill."
"Nothing is unkillable."
Perturabo's voice held no ripples, only cold logic.
"If there is, then the yield is simply not high enough."
He raised his hand, his finger hovering over the red launch button.
"Coordinates locked: Core of the Salamanders' position."
"Goodbye, brother."
The button was pressed.
Without much warning, an extremely bright point of light appeared in the sky, as if a second Sun were rising over the depression.
It was a Tactical Nuclear Warhead specifically designed for heavy armored targets.
For the Salamander warriors holding their ground, the World lost all sound in that instant.
"BOOM—!!!"
A massive mushroom cloud, carrying the breath of Death, rose into the air on the left flank of the battlefield.
The terrifying shockwave swept through everything, and the temperatures of thousands of degrees instantly vaporized all matter in the central zone.
The earth trembled violently, rocks were melted into glass-like crystals, and even the distant rebels couldn't help but stop their actions, watching in fear as that destructive light consumed everything.
Vulkan's massive frame appeared so small within the white light.
His final action was to spread his arms, attempting to use his own body to shield the sons behind him, trying to use that mortal frame to resist the tyranny of the nuclear fire.
After the light came a deathly silence.
When the black winds carrying radioactive dust blew away the smoke, people discovered with horror that the Salamanders' position had vanished.
Only a massive, steaming crater with a vitrified surface remained.
No bodies, no wreckage, not even ashes.
Everything had been erased.
Vulkan was gone.
No one knew if he was alive or dead, but at the center of a nuclear explosion of that yield, even a demigod-like Primarch, even the Perpetual Vulkan, would likely find it difficult to survive on a physical level.
The main force of the Salamanders Legion was wiped out in this single strike.
Thus, the battle of Istvaan V came to a complete end.
This was no longer a war, but the final curtain of a massacre.
Ferrus Manus had fallen in battle, decapitated.
Vulkan was missing, his fate unknown.
Corax was heavily wounded, fleeing with his remnants.
The once-glorious three loyalist Legions were almost completely wiped out on this day upon the black sands.
Their blood gathered into rivers, staining the treads and boots of the traitors.
Horus stood on high, looking over this field of slaughter, looking at Ferrus's head impaled upon a spear, a complex expression appearing on his face.
The fate of the Milky Way Galaxy, at this moment, was completely severed.