"What's happening?"
Cadian surface. Seventh Armoured Defence Sector.
The hatch of a Chimera armoured personnel carrier was shoved open from within.
A Commissar in Cadian uniform hauled himself halfway out, his violet eyes narrowing sharply as his gaze swept toward the vox-caster array mounted behind the defensive line.
It was the battlefield broadcast system, centrally deployed by the sector command.
Under normal circumstances, that equipment carried either the pre-battle prayers of Ministorum priests or the tactical directives of Supreme Overlord Creed.
Neither of those should ever have broadcast what had just come through the speakers.
"Suicide?"
The man repeated the word under his breath, his voice heavy with disbelief.
Something is very wrong.
Could the Chaos forces be jamming our equipment?
The thought came to him immediately, as it would to any Cadian veteran.
A Chaos tech-heretic or psyker had likely launched some form of directed interference against the broadcast frequencies — a corrupted signal attack, designed to poison the chain of command and erode unit cohesion.
A reasonable assessment.
The only problem was —
"No."
The Commissar's pupils contracted sharply.
Because he saw something.
A soldier was stumbling out of the trench. His steps lurched and staggered, his body swaying in a way that violated every principle of tactical movement — like a civilian who had drunk himself half to death.
But what made the Commissar's breath catch was the soldier's eyes.
Those eyes were burning with cobalt-blue psychic light.
The soldier raised his lasgun.
The muzzle was pointing at his own chin.
"What are you doing!"
The Commissar bellowed and launched himself off the Chimera like a bolt from a crossbow.
His boots hit the muddy trench floor with a heavy thud, sending up a spray of filthy water and ice shards, and he charged.
He slapped the lasgun out of the soldier's hands, then delivered two sharp, ringing slaps across the man's face.
The cracks echoed through the trench.
But the soldier's eyes did not change.
In those eyes blazing with blue psychic fire, pain and terror coiled together — like a drowning man thrashing in the deep, straining desperately toward the surface yet never reaching it.
The soldier's hands rose again. His fingers curved into claws, reaching for his own throat.
"Fight it — this is a Chaos psychic attack!"
The Commissar seized the soldier's wrists and forced him down into the mud.
He had seen this before. More than once. That was what came from decades of service on Cadia.
It was experience. The experience of a Cadian veteran.
The Commissar drove a precise knife-hand strike into the side of the soldier's neck and knocked him unconscious, then straightened up.
He turned.
And saw hell.
The entire defensive line had collapsed into chaos.
The voice was broadcasting simultaneously through every vox-caster, every personal comm-bead, every vehicle's internal vox-system.
It spread like an invisible plague, carried on sound itself, propagating through the air with terrible speed.
People were falling every moment.
A logistics trooper carrying artillery shells suddenly stopped. His eyes went glassy and vacant in an instant; cobalt light surfaced from somewhere deep behind his pupils. He set down the shells. He drew the combat knife from his belt. With an almost ceremonial slowness, he pressed the blade against his own throat.
The blade drew across.
Blood sprayed.
The trooper's body crumpled into the mud, his head lolling at an unnatural angle, a ragged wound blossoming across his neck.
And the ground around him was already covered in bodies lying in the same positions.
The Commissar looked down the line.
By some mercy, not everyone was dying.
The real Cadian veterans — those warriors who had fought for decades in the shadow of the Eye of Terror — were holding on.
He saw a scarred sergeant grinding his teeth, both hands locked around the edge of the trench, his fingernails torn back from the pressure, blood running down into the dirt.
But there were too few of them.
Cadia now held reinforcements drawn from every sector across the Segmentum Obscurus.
Mordian Iron Guard. Valhallan Ice Warriors. Tallarn Desert Raiders. Countless logistics and support personnel supplied by foundry worlds across the Imperium.
Their will to fight was perhaps just as resolute — but they lacked experience. They had never truly faced Chaos before.
And so, the moment that voice reached them, they fell like cut wheat.
The Commissar's fists tightened.
In his violet eyes burned a flame of cold fury.
Meanwhile, deep in the Warp.
Adam spun around.
In the immaterium, distance carries no meaning. Neither does time. Past, present, and future are tangled here into a web of chaos that no rational mind can unspool.
What Adam felt now was a surge. A tide.
A tide of death.
On the surface of Cadia, tens of thousands of lives had been extinguished in a matter of moments.
Their souls, freed from their bodies, tumbled into the Warp trailing the fear, pain, and delirious anguish of their final seconds. The combined weight of those emotions struck the immaterium like a boulder dropped into a still lake, sending concentric ripples cascading outward through the Warp.
By the standards of a true Chaos cult sacrifice, this death toll might be considered modest.
But Chaos does not concern itself with scale.
"Emperor!"
Adam roared, and golden psychic light detonated from his body.
"I am here."
Then, from behind Adam , a far vaster torrent of golden energy surged forward.
The power of the Master of Mankind reached across uncountable light-years from the Golden Throne on Terra, travelling through the paths of the Warp and arriving here in an instant.
That golden radiance reached out like an invisible hand directly into the region of the Warp corresponding to Cadia.
Suppression.
Purification.
Containment.
The psychic waves raised by the mass hysteria and the self-destruction it had induced began to recede at visible speed under the weight of the Emperor's will.
The spread of emotional contamination was compressed to its minimum possible extent.
"It appears this is a psychic plague of Tzeentch's own crafting," the Emperor's voice came again — this time without the emotional weight of before, cold and analytical, as though delivering a report. "The architecture is Tzeentch's, serving as the spell's foundation, but there are contributions from Slaanesh and Nurgle as well. Tzeentch's psychic framework forms the base structure; Slaanesh's power has amplified the self-destructive impulses within each afflicted mind; and Nurgle's plague principles have enhanced the rate of transmission throughout the entire working."
"How heartwarming. What profound fellowship."
Adam allowed himself a brief smile. "I never thought the day would come when all four Chaos Gods worked in such harmony."
His gaze moved outward — to that point in the Warp that corresponded to the position of Cadia.
The moment Adam reached out his hand, before he could do anything at all, his head snapped to the side.
"Impeccable timing, as always —"
The Four Chaos Gods struck again.
Khorne's Brass Axe split the veil of the Warp; Tzeentch's mutating fire wove an endless labyrinth of illusions; Nurgle's plague-pus surged forward like a river of rot; and Slaanesh's whispered temptations reached for every last crack in his defences.
The Emperor's power had just been diverted to suppress the Warp-surge over Cadia in order to contain the psychic contamination — which meant Adam had no choice but to pull every part of himself together and focus entirely on standing against these four torrents, each of which was sufficient to grind any living thing to dust.
And this, without question, gave Chaos exactly what it needed.
The Warp surged again.
This time more violently than before.
Somewhere on the surface of Cadia.
A Warp rift tore open in perfect silence.
It simply appeared in mid-air, as if an invisible blade had drawn a wound across reality. Its edges burned with fire — blue, purple, green, red — four colours intertwined yet absolutely distinct from one another.
A massive, twisted rune floated out through the rift.
Across its surface ran currents of pure Chaos energy; every line of it constantly shifted shape, as if the rune itself were a living thing.
An ordinary human who looked at it for even a moment would find their mind shatter, unable to process structures that violated every law of physics.
Then a vast figure stepped through the rift.
His skin was crimson throughout. Armour of blue and gold covered him from head to foot, every plate carved dense with Chaos runes that writhed, shifted, and whispered without ceasing — as if a thousand mouths were simultaneously chanting hymns of desecration.
In his hand was a great sorcerer's staff.
At its tip was not a blade or a crystal, but a book bound in chains. Its pages turned without wind; with each turn, blue psychic flame poured from the paper.
The Daemon Primarch of Tzeentch. Magnus the Red's single eye swept across everything around him, and then he gave a slow, satisfied nod.
All things considered, his plan was proceeding smoothly.
Change is part of Tzeentch.
And the change of plans is itself a form of change.
Even if the Imperial countermeasures had significantly exceeded what Magnus and the other Daemon Princes had calculated, even if the upheaval of Cadia itself had been a crushing blow to the plans of every Chaos faction —
What did it matter in the end?
All your efforts are in vain.
Magnus still stood here. On the surface of Cadia.
Of course, none of this had been planned. In a sense, it was improvisation.
Magnus's original plan had been to support Abaddon — his poor nephew, blessed by all four Gods simultaneously and abandoned by all four simultaneously.
If the Warmaster of the Black Legion could, with Magnus's support, succeed in destroying the Pylon network, that would have been the ideal outcome.
But with the Eye of Terror itself under threat, Magnus now found himself obliged to make a regrettable adjustment.
Hold on just a little longer, my dear nephew — keep the line and there's still a way through!
I'll come to your aid in due course!
But then again.
If the operation to make Cadia fall succeeded, it would equally satisfy his plans — Tzeentch's plans — would it not?
This was change.
This was the essence of the path of infinite change.
And around him, more rifts were tearing open.
Daemons beyond counting poured from the Warp — Tzeentch's Pink Horrors and Blue Flamers cackling as they flew; Khorne's Bloodletters and Flesh Hounds baring bloodthirsty expressions; Nurgle's Great Unclean Ones and Plague Drones moving with a sluggish, rotting patience; Slaanesh's Keepers of Secrets and Daemonettes spinning in light, fluid dances.
Their numbers blotted out the sky.
And at their backs, an even vaster Chaos daemon-army was massing.
Those twisted, mutated monstrosities — humanoid things utterly remade by the power of Chaos — screamed and howled with ear-splitting fury, turning the entire surface into an ocean of madness.
Magnus's single eye turned toward the distance.
There, a massive column of green light was surging into the sky.
The location of Cadia's underground facility.
That green radiance was continuously repairing the great wound in the fabric of reality — the Eye of Terror itself.
Some ancient artefact of the Necrons, brought from the Battle of Heaven, was operating in a manner beyond comprehension, slowly, inexorably stitching closed that vast tear that had ripped through the galaxy for thousands of years.
Magnus's eye grew more intense.
That was his first target.
Destroy that facility, and the Eye of Terror would endure forever.
And what good was that troublesome iron skull holding the line in orbit? What use was any of it?
The fall of Cadia that followed would become one of the greatest victories he had ever inscribed in the material universe.
Filled with satisfaction at the thought, Magnus raised his staff and began to cast.
Nine hundred and ninety-nine distinct spells unfolded in his hands. Psychic energy cascaded from his body like a waterfall; each spell was complex enough that it would take the Imperium's finest psyker a lifetime to fully study even one.
But for Magnus, these were merely rudimentary techniques, called up without effort.
To move mountains and fill seas, to shift stars and reshape the heavens —
For a Primarch who had devoted his entire existence to the mastery of the psychic arts, these were not hyperbole. They were direct, literal descriptions.
And yet every single spell failed.
A flicker of confusion crossed Magnus's single eye.
He adjusted his parameters. Rebuilt his spell-model from the ground up. Attempted to pierce the veil between reality and the Warp from different dimensional angles.
Another nine hundred spells.
Another nine thousand.
Each attempt was a masterwork in its own right. Each casting would have reduced any mortal psyker to awe-struck silence.
All of them failed.
Magnus's sorcery could not reach the location of that facility. He could not teleport any portion of his daemon-army there.
The reality veil over that area was solid to a degree that defied all reason, all experience. The power of the Warp was completely sealed out.
Magnus calculated continuously. Then he grasped something deeply alarming:
Based on the veil-thickness he had been able to probe — the density of the barrier between the Warp and the materium at that location — any daemon-troops he led anywhere near that point would almost certainly be severed from their connection to the Warp the moment they approached. They would come apart on the spot, dissolving into meaningless, incoherent energy.
Magnus stopped casting.
His single eye locked onto that column of green light roaring into the sky.
Then it came to him.
"Impossible."
For the first time, the Daemon Primarch's voice wavered.
"That is... the Necrons' Ghostkeel Deadzone?!"