In the aftermath of the battle, while the wounded were tended and the dead gathered, Grand Master Voldrus and his Grey Knights began the solemn task of preparing the portal to the Imperial Palace Librarium. Every sigil, every inscription was etched with exacting care, the air thick with consecrated oils and the low drone of protective chants.
In a shadowed corner of the war-torn chamber, Seiji and Naon knelt beside Bruno's makeshift medicae station. Blood and soot smeared their masks and armor, the stench of warp-taint clinging to every breath.
"His condition's worsening," Naon murmured, voice tight. Bruno writhed, his breath ragged, the stump of his leg darkening unnaturally. "The wound… it's not natural."
"Warp infection," Shinji, their field medic, spat, tone bitter. His gauntlet tools flickered to life as he scanned the wound again. "We trained for every toxin, plague, chem agent, and psi anomaly. But not this. Not a wound that breathes corruption back at you."
Seiji's jaw clenched. He tapped the communicator built into his collar. "Silent Veil, this is Commander Seiji. Request immediate evac for medical quarantine. Respond."
Static.
Again.
Nothing.
A heavy silence hung between them before Seiji lowered his hand.
"They're gone," he said flatly. "Or too far to reach."
Around them, the air itself felt wrong. The signs of warp corruption spread in subtle ways at first — then unmistakable. Skin paling. Veins blackening. Eyes glassy with fever. Even among the hardened Astartes and ancient Eldar, the taint left its mark. The taste of copper and madness clung to the air like a film.
Seiji's gaze swept the chamber, landing on the conclave of Astartes Librarians nearby — battle-psykers in ceramite marked with psychic wards. He strode toward them, ignoring the weariness in his limbs.
"Librarians," he addressed them formally, "I request your expertise. My men — and not just mine. Everyone here is touched by the warp. We need this purged before it festers."
The lead Ultramarine Librarian exchanged a glance with his brethren. Then, as one, they turned their helmed gaze to Guilliman, awaiting his consent.
The Primarch gave a curt nod, his expression carved from stone.
"Do it."
At that, the Librarians moved. Forming a circle, psychic haloes ignited above their helms, their incantations merging into a single pulse of warp-light. Cleansing tides of force swept over the gathered survivors. The corruption clawed and shrieked against it — but something lingered, stubborn and mocking.
A final curse.
"You think this victory yours?" a guttural voice rasped through the warp, not aloud but in every mind present. "I am wrath incarnate. You are but kindling for the fire."
The curse resisted the psykers' best efforts, dark tendrils refusing to break.
Guilliman's eyes narrowed. The thought of losing men — no, allies — to a daemon's spite gnawed at him. More than that, the idea of letting Skarbrand have the last laugh was intolerable.
He sought within himself. Past the ache of battle, past the cold logic of command, past the bitter rage.
And something answered.
A golden light burst from Guilliman's form, searing through the chamber like dawn breaking the night. It blazed against the daemonic residue, the darkness recoiling in a shriek of unseen horror. The corruption evaporated in an instant, scoured not by psychic power but by something higher — the lingering touch of the Emperor's light.
For a breathless moment, the chamber fell silent.
Even the Grey Knights faltered in their chants, momentarily awed.
A Guardsman whispered hoarsely, "The Emperor's light…"
Others dropped to one knee. Some wept openly. Ultramarines lowered their helms in reverence. Even a few battered Shinobi paused in grim recognition.
Guilliman scowled.
"Fools," he muttered under his breath. Not for their gratitude — but for what it represented. Another link in humanity's endless chain of superstition.
Inside, he too was unsettled. That light. Its source. Had it come from him? Or through him? Neither answer sat well.
Naon, watching the display, felt a twist in her gut. For all the Exiled's Golden Age relics and war doctrines, all their precision — they had nothing like this. No countermeasure for warp-spawned malice that clung even after battle. A blind spot that even ten millennia of careful observation hadn't been noticed.
A flaw.
A fatal one.
Seiji felt it too — a sharp awareness of the weakness they'd tried to ignore. All their teachings, for all their strength, remained combat-focused. Their medics knew how to treat wounds, purge toxins, and patch psi-burns. But not this. Not something that bled madness with every pulse.
'We have gaps,' Seiji thought grimly. 'And we've been pretending we didn't.'
His reflection was broken as Grand Master Voldrus approach, his silvered armor stained with ichor and ash.
"Lord Guilliman," the Grey Knight intoned, voice heavy with ritual weight. "The portal stands ready. On your command, we leave this cursed place."
Guilliman's gaze swept over the battered survivors — bloodied Astartes, weary guardsmen, grim Shinobi, and wary Eldar. For all their divides, in this one cursed place, they'd fought side by side.
He sheathed his sword.
"Then let's see it done."
In the shadows, Seiji's thoughts twisted.
Ten millennia of watching this Imperium… of stolen dataslates, dissected xenos artifacts, purged Mechanicus archives… and still… we underestimated this.
Warp corruption.
An enemy no machine could predict. No Golden Age code could unmake. His people were masters of combat, infiltration, weapons beyond the Adeptus Mechanicus' wildest dreams — but their medicae doctrines were pragmatic, combat-focused. Wounds. Poisons. Trauma. Psi-burns. Biological weapons.
Not this.
'Our greatest flaw,' Seiji admitted to himself. 'Ten thousand years of secrets — and we forgot the oldest truth: the warp doesn't care for logic.'
He met Naon's gaze. Behind their masks, the same realization.
This war would change them. One way or another.
And from beyond the portal, the Imperium awaited.