'Kaurtal,' the thing behind him rasped. 'You abandoned the Legion.'

First there was light acid-strong, acid-bright. It was light at its absolute transcendence, the very apotheosis of illumination's concept, too bright for mortal reasoning.

He had only one thought through the dissolving burn of incomprehensible brightness, and that was a simple one: this was death.

The light finally allowed other sensation to trickle through. He heard wave crashes and screams; the cries of men, women and monsters drowning and burning in an ocean of the same white fire that threatened to swallow him.

A cracking jolt brought him back into the chamber. Ward runes and their more pervasive counterparts sigils used to summon lined the walls at uneven intervals, many overlapping their cousins. Some were cast in brass, others no more than glyphs knife-carved into the dark iron of support pillars. He reached to grip the blade impaling his chest. His fingers closed around the metal, but he could not pull it free.

Kaurtal staggered, his eyes flowing over the chamber once more. Here was the abode of muttering human priests and chained astropaths twitching in fluid-filled coffin pods, forced to live lives of endless slumber, so others might harvest their eternal dreams.

A human soul was a candle in the endless ocean of the warp. A psyker's soul was a conflagration, as dangerous to the Neverborn as it was tempting. It could be harnessed. Except that was not the right word, was it? Not harnessed, nor even channelled.

No, it could be weaponised.

Kaurtal had never been told this no one spoke of such things, and he sensed his comprehension was incomplete yet he knew all of this implicitly, the moment he opened his eyes and bore witness to the clanking, grinding pods and their captured cargo.

He knew it because...

...because there was Something Else inside his head, melting its thoughts into his. With the same ice-lance plunge of lore from nowhere, he knew the taste of a thrashing soul between his teeth, and how terror only spiced the flavour.

Nerkhulum, said the Something Else inside his mind. You are a weak host, but we shall see how this game ends.

Kaurtal's attempt to speak left his lips in a gush of blood. Argel Tal pulled the sword from his chest in a clean yank, letting the Custodian blade's power field sizzle away the blood marking the metal.

That is my blood, Kaurtal thought, watching it bake away into smoke. He fell to his knees, back on board the Fidelitas Lex, but still somehow surrounded by the crashing of waves and the shrieking of souls.

He felt his skin sloughing free with the sound of ripping leather. Bones cracked and split and pushed up, up, up through his body.

His scream had joined the others, and Sergeant Jerudai Kaurtal of the Twisting Rune Chapter died upon the deck of his pri-march's flagship.

The dead encircled him, walking in weak-kneed staggers, coughing dust from their helm's rebreather grilles. Most carried no weapons, though a few still clung to rusted blades with the tenacious instinct of muscle memory.

No denying it now. No claiming it was a hallucination brought on by cranial pressure, or the disorientation of radiation poisoning. More of them were still rising from the dirt never the Ultramarines, only the warriors in red. His own brothers.

'Kaurtal,' they wheezed, dry voices cracking over the vox. 'You abandoned the Legion.'

Even the dead accused him. He railed back at them, cursing, frothing, spitting. Corrosive saliva sprayed from his fanged maw.

'The Legion abandoned us! I will make them remember the fallen!'

The lead figure bore the crest of a captain. Holes glared emptily where eye lenses had once shone clean and blue.

'Death will free you of delusion,' the revenant breathed.

'And of self-pity,' wheezed one of the others.

'You run from duty,' the captain pointed at him with a shaking, rattling hand. 'You run from what the Legion asked of you.'

'And you call it courage.' Yet another corpse staggered closer, its head angled wrong, on a broken neck. 'You run, but call it courage.'

'You cower, but name it virtue.'

'You betray, but name it justice.'

Kaurtal roared at the advancing remnants, more spit flying from his teeth and the black snake that had been his tongue. The Change should have come easier now that Nerkhulum was awake, melding his body flawlessly into its divine form, and yet he felt the daemon's sluggishness drag against his muscles, a lactic burn resisting his every effort.

Stop fighting me, he sent within, in a convulsion of panic. His wings beat in futility, as bones shifted and slid beneath his skin.

You are a weak host. Nerkhulum's voice was as sharp and nasty as the pain of his straining muscles. And now we see how the game ends.

The first of the dead Word Bearers made a graceless lunge for his throat, corroded fingers breaking against his armoured gorget. Kaurtal killed the thing in reply, smashing it to the ground with a bone claw and grinding its helm beneath his boot.

They marched through the dust some staggering, some managing to make a stumble into something resembling a run. Kaurtal's bolter kicked and boomed, slamming explosive shells into the closest figures. The Word Bearers burst and shattered, falling into the dust, naming him a traitor even as they dropped in withered ruin. It made no difference. Their hands rose from the ground, trailing dust as they clawed over his boots and greaves. Sparks flew from scraping fingertips. They came on in a choking, gasping tide.

Kaurtal turned, took three running steps to shoulder-barge his way through the husks blocking his path, and launched skyward with another roar. This one sounded dangerously close to a cry for help.

He crashed back into the dirt, colliding hard with the debris miring the ground. His helm struck rockcrete, painting it red, and a lance of cold metal rebar pounded through his collar, leaving him choking on rusted metal, gagging for air that would not come.

Any scream he would have voiced in shame was stolen by the iron impaling his throat. The only sounds he made were gurgling grunts as he jerked his head back, trying to wrench himself from his impaling.

The fire in his wings started a second later, as his nervous system caught up with the reason he had fallen from the sky. One of the dead warriors had cut a wing clean from his back. Kaurtal could hear the insectile buzz of an active power sword.

He knew no fear. He knew no fear. He knew no fear.

'Wait,' he growled from a blood-bubbling throat. The iron-on-bone grind of pulling himself free felt worse than the smacking kick of impact. 'Wait.'

Such a weak host, the daemon said again. Destined for treachery. Your resolve will break. Must I be strong for both of us?

Nerkhul In that moment he was swallowed, somehow, inside his own mind. He felt it as a compacting of sorts, an enclosing.

You betray your brothers, and now you would beg me for succour? You are more maggot than man, Jerudai Kaurtal of the Seventeenth. Not a warrior, but a worm. I have no desire to be bound within such a feeble vessel.

Kaurtal screamed with no mouth and cried out with no voice. He was still trying to shriek when the walking dead fastened their rusted fingers upon his armour-plating, and pulled him down into the blackness.

Jerudai Kaurtal never stood back up.

Argel Tal waited with the body for almost an hour, pacing the ornate chamber with his weapons sheathed, arms folded across his breastplate. His boot-steps sent tremors along the deck grating. The servitors were too mind-locked to pay him any heed, and the chanting thralls too lost in their fever-dream vision quests, but a few of the robed menials flinched back when the Crimson Lord glanced in their direction. The Word Bearer had nothing of anger or irritation upon his features, but since Isstvan he had noticed few humans could stand to look into his eyes. They sensed the daemon within his body, lurking behind his gaze, and his second soul fed upon their fear.

It could have been the same with Kaurtal. It should have been.

But Sergeant Jerudai Kaurtal remained dead on the deck. Not without regret, Argel Tal nudged the body with his boot.

'He's dead,' said a gentle voice from the chamber's doorway. Too gentle to be mistaken for human, yet too resonant ever to be called weak. Argel Tal turned to the unexpected intruder, lowering his head in reverence the moment he caught sight of the filigreed red ceramite armour. 'Truly dead, that is.'

'My lord, I cannot do this.'

Lorgar Aurelian, primarch of the Word Bearers, rested a fatherly hand upon his son's shoulder. The last time Argel Tal had seen him, that scholarly, reserved, gold-inked face had been decorated in the blood speckling of a hundred dead Raven Guard. Now, it was warmed by a patient smile.

'You have walked the roads of Heaven and Hell, my son. You can do anything. What troubles you?'

Argel Tal nodded down at Kaurtal's slain form. 'They keep dying, father.'

'So this is not the first?'

Despite himself, Argel Tal gave a rueful little smile. 'No. This is the thirteenth.'

'I see.' Lorgar lowered himself into a crouch, his black cloak trailing over the decking. With delicate care, he closed Kaurtal's staring eyes. 'How many have lived?'

'Three,' admitted Argel Tal.

'The daemons are rejecting them as hosts,' Lorgar postulated, rising to his feet again to tower above his son.

Argel Tal nodded again. 'Physicality alone is not tempting enough for them to incarnate. They desire strong vessels to enter into symbiosis. Kaurtal babbled as he died, speaking of Calth, prophesying nonsense through the blood running between his teeth.'

That raised Lorgar's immaculate eyebrow, and brought a shine to the edges of his tawny eyes.

'He saw one of the many paths of the future?'

Argel Tal could only shrug. 'I believe so. It seems to be how the daemons test their hosts letting glimpses of the future unwind, and judging the warriors' reactions.'

Lorgar was silent for several moments, his armoured fingers tapping on the skin-bound book chained to his hip. The stretched, cured faces stared at Argel Tal in eyeless, slack horror.

'Perhaps it is a blessing that Sergeant Kaurtal died. It seems that he may have made some foolish choices in the future.'

Argel Tal drew breath to agree, then pulled up short. 'Father,' he said. 'I can't do this.'

'You are already doing it. Give me three Gal Vorbak for every thirteen dead, my son, and I will thank you until the stars themselves die as icy cores in the void. We are demanding more than any legionary has ever been forced to bear. Let us not weep at the weaklings falling by the wayside.'

Argel Tal fell silent, looking down at the corpse. He had been sure of Kaurtal.

Kaurtal, who had no mundane, military ambition, beyond pride in his prowess. Kaurtal, who had slaughtered countless dozens of Raven Guard on the killing fields. Kaurtal, who had knelt in prayer, scourging his flesh for not killing enough, chanting amongst the dead in the hours after Isstvan. He had had palpable humanity beneath the iron of his faith, beneath the ceramite of his Legion. Not in the sense of a humane soul, or the capacity for mercy Kaurtal was far past such weakness. It was merely that he possessed a measure of human foundation at his heart, and Argel Tal had hoped that it would appeal to the Neverborn, to mesh into symbiosis with such a spirit. A brutal warrior that had never known defeat, with a vulnerable soul. What better fodder for the children of the gods?

'I wonder what he saw,' Lorgar mused.

'One of the survivors saw Calth a war in the tunnels beneath the surface. Another saw the night we stood chastised before the Emperor. The other claims that he saw nothing at all, and I allowed him that one white lie, given what I'd made him endure.'

Lorgar chuckled at that. 'I suppose they will all see what every prophet sees lies and metaphors, hopes and promises, all seeded with the ghosts of truth. Such is the way of all prophecy.'

Argel Tal could not disagree with that. He gestured to a pack of cowled menials.

'Arrange for lifter servitors to remove this body, or drag it yourself if you can muster the strength between you.' His dual voices held a dissonant harmony, almost meshing, but never quite becoming one. 'Take it to the apothecarion for gene-seed removal, and have the rest incinerated.'

They approached bowing, scraping, whispering a stream of mumbled reverence in Lorgar's direction without raising their eyes.

'Do not look amongst the ranks of our best warriors,' Lorgar said, once the thralls were gone, with the corpse dragged away between them. 'That's where you're going wrong.'

Argel Tal looked up at his father, lost by the words. 'I don't understand.'

'I want two thousand of these daemon-souled warriors, my son. Two thousand, before we reach Calth, one year from now.'

Two thousand. Two thousand.

Argel Tal gaped. 'Lord Aurelian, I can't...'

'You can.' Lorgar's eyes were flint. 'I do not want our best warriors to be thrown at Calth. We will need the strongest and finest Chapters to reeve our way through the rest of Ultramar. Do not use our best blood for this game, Argel Tal. Use the ones that loathe the Ultramarines beyond balance, beyond reason, beyond sanity. Let the daemons come, drawn by the hatred in the hearts of wrathful men. Emotion attracts them as much as devotion. Remember that.'

'Practically half the Legion still prays for the Thirteenth's annihilation, my lord.'

'Exactly,' Lorgar nodded. 'Use that emotion. Use them. We can perfect the process later, before we begin whoring our best warriors' souls away.'

Understanding dawned in Argel Tal's mind.

'You do not want warriors that know no fear. You want warriors that know no forgiveness.'

'Delightfully phrased,' Lorgar finally smiled, 'and true to the last word.' The primarch turned to leave, but hesitated. Ripples waved their way down his sable cloak. 'The entity that judged Kaurtal an unfit host. What was its name?'

'Nerkhulum, sire. Why do you ask?'

Lorgar waved away his son's concerned tone. 'Because I can hear the creature laughing in the warp's song, and this chamber still rings with the echoes of its power. That makes me curious, Argel Tal. Butcher one of the injured men in the apothecarion and bind him into a Dreadnought shell. I want to see if Nerkhulum can be enticed with stronger bait.'

Argel Tal, to his credit, needed several moments before he committed himself another step further along the road to his own damnation.

'It will be done, my lord.'

'If you need me,' the primarch turned away, 'I will be on the Conqueror, with my brother.'

MESSAGE #3314157.883 AUTHENTICATED:.

ALCAEUS, F. (Captain, XIII Legion)

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