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Ahriman: Undying – Extract

A Black Library Publication

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I

EATER OF MEMORY

Battle-barge Hekaton, the warp
Relative chronometric position: 21

Ctesias felt his daemons burn on the other side of the door. Fire boiled across his inner sight. He staggered. His fingers smeared blood down the iron of the portal. A psychic force hit the door. Wards melted and molten silver ran down the frame. Ctesias did not see it. His mind was alight, his senses shrieking with the sympathetic sensation from the daemons as they were blasted to ash and went tumbling into the warp. They were greater entities of their kind. They had broken kingdoms and armies across time. They were amongst the most lethal of their kind that he, a summoner of daemons, had encountered.

And now they were gone.

Obliterated.

Removed from reality as if they had never been.

‘No…’ he gasped. ‘No!’ His ears rang. There was blood running down his chin. He could taste the copper and iron in his breath. Pain arced up and down his limbs and through his torso. Images blurred and smeared across his sight. The walls were glowing. He could feel the pressure building in the warp outside the walls of his sanctuary. Beyond those walls the battle-barge Hekaton plunged on through the immaterium. He blinked and saw the column of fire burning across his mind’s eye. It was coming closer, howling, sucking in power.

Pyrodomon. The Rubric of Ahriman incarnated. The end and the salvation of the Thousand Sons.

Ctesias laughed, then coughed blood froth.

This was how he ended. Not ripped apart by the daemons he had enslaved, not falling under the guns of the Emperor’s deluded warriors, not undone by a mistake in a summoning, but made into nothing by the Rubric he had helped create.

‘Not much time,’ he muttered and began to draw together his remaining strength.

He had taken this sanctuary on the Hekaton and made it strong. It was a series of chambers close to the ship’s heart. He had armoured it against assault by daemon and psyker. He had done his work well. There were others… had been others amongst the Thousand Sons who had a greater theoretical understanding of abjuration and warding than Ctesias. None of them had his practical understanding and experience, though. His art had chained great princes of the warp and kept him safe from the sorcery of rivals and vengeful daemons. The sanctuary was as secure as he could make it, but it was moments from breaking open. It was inevitable. Ctesias had one thing he needed to do before it did.

‘Come on,’ he snarled at himself.

He tried to stand. His limbs would not move. Numbness was already spreading through him. He was burning from the soul outwards. Everything was slowing, blurring to calmness even as it tumbled into ruin. Last moments… Last beats of his hearts.

The bones hanging from the ceiling were rattling under the growing psychic pressure. Stone statues set in niches were weeping pus and blood. Liquid boiled in jars and vials. Smoke rose from scrolls heaped in the corners. He could hear the daemons bound into the objects screaming to be free. In his mind, the pieces of daemonic true names beat against their separate cells of thought. They could all feel the inferno coming. The wards worked into the sanctuary’s walls and doors were breaking. They would not last more than a handful of seconds. The empyric energy would overwhelm the chamber and everything in it. Then the fire of Change would pour in. The daemons held in their prisons of stone and metal and bone would be torn apart and scattered on the pyre wind. A life’s work reduced to dust…

The thought brought another cough of blood and laughter to his teeth. Many mortal lifetimes spent bartering your soul for knowledge and power, and what good has it done you? he thought.

A sound of shearing metal rang through the chamber. A crack had opened in the metal of the door. An orange furnace light reached through the gap. The daemons were screaming at Ctesias from inside his head. Frost was gathering at the centre of the floor. Flakes of ice spiralled. A glass cylinder holding a taloned hand shattered. Fluid gushed out and then flashed to steam. The hand scrabbled at the deck.

Ctesias could feel the fire kindling in his guts and thoughts. The cracked door buckled. Molten metal drooled onto the floor.

‘Move, you old fool!’ he snarled, and forced himself up. Pain exploded through him, shattering his thoughts for a second. He swayed. Another telekinetic blow hit the outside of the door. He could taste ash on his breath now. He staggered across the chamber. His hand caught on the stone shelf before he hit the ground. White spots were blooming in his sight. He raised his head and gripped the stone jar on the shelf.

‘Al’cul’narathros…’ he said, pulling the name from the dungeons of his mind. The jar shook in his grip. It was shaped like a coiled snake, its top a fanged mouth. The wax sealing its throat melted at Ctesias’ words. ‘Nu’sha’crel… I call and summon you from your cage.’

Black smoke poured from the jar’s mouth, boiling through the air as the daemon manifested. Amethyst-and-orange eyes shone in the cloud. Shadow claws clutched and clicked, shedding frost from their tips. The daemon looked at Ctesias. Loathing fumed from it. It was a thing born from the desire to forget: the wishes of soldiers to put down the burden of what they had seen and done; the prayer of a soul at the end of their days, hoping to die with a clear conscience; the pleasure that came from only remembering the good and forgetting the bad. All these moments had created and shaped the daemon. It was an eater of memory. Ctesias had bound it long ago but had never called on its power. He had notions that he would use it as a weapon against an enemy or rival. He had not thought that he would unleash it on his own mind.

‘By the bindings that hold you, I command you now,’ said Ctesias. The daemon squirmed.

Another blow on the door, and now the crack was a wide fissure in the iron. Ctesias felt the daemon’s desire to flee. It pulled away. Ctesias lashed out with his will. The daemon snapped back to its place. Teeth of ice formed in the smoke of its form. It hissed with anger.

‘Take what I command and carry it to oblivion,’ said Ctesias. He closed his eyes and set his will. The command was silent, but the daemon heard.

The door gave way. Chunks of molten metal spun through the air. A gale tore into the space. The last wards in the chamber collapsed.

‘Now,’ Ctesias said, and opened his eyes and mouth wide.

The daemon plunged into him. The black smoke of its body poured past his teeth and down into the pit of his mind. He felt its jaws close on the memory he had commanded it to take. Pain. Pain beyond what was possible in the physical realm. He was screaming, he realised, screaming with mouth and mind. Then he felt the daemon tear free of his thoughts, the scraps of the memory it had eaten dissolving into jumbles of word and images without meaning…

Black and red… Crow beak… Falling…

An invisible wall of force picked him up. He felt his armour crack with the impact. He struck the wall, limbs splayed, pinned in place.

Figures came through the molten ruin of the door. Yellow-and-blue flame coiled over their armour. The eyes of their helms were holes. Fire roared in the void beyond those openings. He recognised them, or at least who they had been: Ignis, Gilgamos, Lycomedes… His brothers in the high circle of Ahriman’s Exiles, and his apprentice. They were gone, though. The things that walked towards him now had only one name.

The three figures stopped in front of Ctesias. They looked up at him. He could feel heat radiate from them, could smell his own flesh charring inside his armour.

+Where is he, Ctesias?+ asked a voice that spoke in his thoughts. +Where is Ahriman?+

‘In all honesty…’ he said, and forced a grin to his lips, ‘I do not know.’

He felt the fire stab into his mind then. Telepathic blades cut into memory and peeled open his secrets. The pain was not as bad as he thought it would be. He coughed again, felt blood spatter down his front. ‘Surprising though it may be, I am telling the truth. You can’t take what I don’t have.’

The three figures looked at him. They were statue still. +We will find him. Even with the memory of what he did to escape torn out by a daemon, we will find him,+ they said. +It is only a matter of time, and time is irrelevant. We are the Thousand Sons, and we are eternal.+

‘Irrelevant?’ Ctesias held the smile on his lips. ‘If Ahriman is irrelevant then why are you trying to find him?’

+He is one of us.+ The figure who had been Lycomedes stepped forwards. Ctesias could feel the fire rising inside him now, blazing, swallowing the last sensations of flesh, blanking his mind with a white-hot brilliance. +As are you… Ctesias.+

And then there was just the fire and the sound of his name following him down as he fell, hissing around him like ash blown on the wind. Like dust.

The remains of Ctesias held to the wall as the pyre burned through them. The flesh inside the armour vanished within the first second. Flames blazed from the collar and the limb joints. Tongues of magenta, cyan, and orange flowed over the plates of ceramite. Shape and form altered. Substance grew from air: silver, sapphire, gold. The three figures held still as the fire reached a point of white incandescence. Then the flame dimmed, draining back within the armour. The etheric force holding it against the wall released. The armour fell… and landed in a kneeling crouch. Then it rose. It was no longer the armour of Ctesias. Gone were the sigils and words that had crawled over its plates. Patterns of fire flickered over sapphire. Golden snakes ate their own tails across its pauldrons. A helm now closed the armour’s collar, and fire blazed from the holes that were its eyes. The figure that had been Ctesias moved to join the others, then they turned and left the room as one. Behind them, the daemons caught in their prisons of bone, glass, and stone shrieked as an inferno drowned the chamber.

The Key of Infinity, boundary zone
Relative chronometric position: 22

Horkos opened his eyes.

Blackness.

The sound of his breath inside his helmet.

Horkos turned his head. The servos in the collar of his armour buzzed. Power… The armour suit still had power, or the servos would be dead. He blinked to activate the helm’s lens display.

Nothing.

Horkos breathed in again. The air tasted of sweat and metal. He understood what the taste denoted: that he had already breathed that same sip of air. The armour had scrubbed and reprocessed it many times. If that circle stopped, so would Horkos.

Horkos… The name rose in his thoughts repeatedly, like a shout fading to an echo. Horkos let it echo on.

Hold on to that name, said a thought. The name is safety.

Horkos blinked again. The helm display did not light. The armour must have gone into an emergency low-power mode. He moved his fingers. The servos in the gauntlet activated after a heartbeat delay. Horkos stilled his hand. If the armour’s power level was critical, then any movement would shorten his life.

Inhale.

‘Activate helm display,’ Horkos said.

A pause, longer than a breath.

A dot of green light appeared in the left lens, a finger-width from Horkos’ eyeball. The golden dot flashed and then expanded into a screed of green code. The symbols flickered as they scrolled across the dark. Horkos did not breathe. The armour was fighting to obey his command. The code vanished. Icons appeared. Information flashed and stuttered red.

Armour integrity: unknown…

Power supply: unknown…

External atmosphere: unknown…

External threat status: unknown…

Horkos absorbed the warnings. He could not remember the events that had led to this point. He knew facts, but not causes. He was Horkos. Horkos was a warrior created of the Legiones Astartes, one of the Space Marine Legions created by the Emperor. Horkos had fought against both the Emperor and the Imperium. Horkos was a psyker, his mind able to interact with the other dimension known as the warp and use its power to break the laws of reality. Horkos’ armour was battered. Old blast and blade scars marked the ceramite plates. The helm was beaked and scorched black. The helm of a crow… Horkos was a renegade, a vagabond warrior who served warlords in the Eye of Terror, a region where the warp mixed with realspace to make a hellscape and a refuge for renegades and traitors. A refuge for creatures like Horkos. All these facts and more were there in his mind, but nothing else.

No… no… That was not right. There was something else, an image at the back of Horkos’ mind, the image of a stone door. Horkos’ thoughts recoiled as the door seemed to grow.

No! No… Not yet, said his thoughts. He needed to understand the outer world first, and then the inner truth.

‘Show external view,’ said Horkos. Green static fizzed across the black view and then drained to the edge. Light poured in. He shut his eyes for an instant at the glare. When he opened them again they had adjusted, and he could see. The light was from stars. The sphere of space surrounded him. The nearest stars were bright, hard points of light, and beyond them the galaxy was a glowing, granular smudge. Their light was coming from all around him.

He was in the void. How? He could have taken a hit from something that had disabled his armour: a haywire pulse, or the blast wave from a void shield collapse. That would account for his armour going into hibernation. If he had been in the outer decks of a void-craft when it came apart, then the blast wave might have thrown him clear – unconscious, spinning in the dark, his armour an inert shell keeping him alive. That was plausible… Except his armour was not damaged. Its main functions had just shut down. And he was not spinning. He was immobile, as though he were lying on a solid surface. Now that he focused on that fact, he could feel gravity tugging on his flesh. Was he on a stellar body? Or even part of a ship? He cut off the thread of speculation. He had a simple way of finding out the truth.

Horkos stood. The armour resisted for a moment, as though it were only half awake and didn’t want to wake further. He straightened with a creak of servos.

Horkos saw where he was. For an instant, his mind rebelled against what he was seeing.

He stood on a layer of black sand, one grain thick. Above him hung the dome of space. A sun burned overhead, vast and blinding, and seeming close enough that Horkos felt he could have touched it. There were other planets too: great gas giants swimming with ochre storms, spheres of pitted rock attended by grey moons. All of them loomed impossibly close, as though the laws of physics did not apply.

The twin beat of his hearts filled Horkos’ ears for a second, and then he willed them to slow. He breathed and heard the echo of his breath in his helm. For the length of that breath, he wondered if he was in a dream, or in the warp itself, floating in a realm made of emotion and thought. As soon as the thought came, Horkos knew that this was no dream or warp vision. He knew the difference, just as someone knew whether water was salt or fresh after only a sip. What he was seeing was real.

‘What type of reality can this be?’ Horkos asked aloud, looking around. No answer came to him. He looked down. Starlight shone through the sand under his feet, glinting between the black grains. A wave of vertigo broke over him. He held his mind steady as it passed. He bent down, aware that there should be no gravity here to allow for either the movement or there to be a downward direction. His fingers scooped up a handful of the sand. For a moment, the stars glared up through the hole he had made. Then the sand flowed over it again. Horkos looked at the grains on his palm. Each one was a regular dodecahedron of dark grey matter. They slid across his palm as he stared at them, spilling from his fingers as though caught by a breath of wind, then settled back into the plateau.

An alarm roared in his helm. He flinched. A red warning blinked in the helm display.

Air supply critical… Failure imminent.

How? The suit’s air reprocessing had been functioning normally only moments ago.

Instinct and conditioning took over. He drew a breath, filling his three lungs. His fingers tingled as his body began to draw blood into his core. The air supply warning flashed brighter. He had just taken the last breath of air his armour could supply. Now he was suffocating. Calm flooded his mind. Panic was one of the human flaws that Space Marines shed when they ascended. A mundane human would already be dying, terror accelerating the process. Horkos’ thoughts became cold, precise, limited to fact and immediate decisions. There were ways that he could survive even without air. His body could shut down non-vital processes and retreat into the sus-an coma that would keep him alive even in the vacuum. But what then? Wherever he was, who would find him here? And what would become of his unmoving body in this place? Would he lie here for as long as the impossible plateau lasted? Would he live past this moment only to die in centuries’ time?

He thought of the sand blowing from his palm… There could be no wind here. He was in the void. This was not a planet or a ship with a shell of atmosphere. This was… What was this place? He looked up at the sun and planets hanging above the horizon. So close, impossibly close. He was not in the normal structure of reality but on its shoreline, somewhere where one set of rules met another.

The air-supply alarm was shrill in his ears. He looked at the external atmosphere read-out. The marker blinked back at him, reading Unknown. Horkos made a decision.

His armour’s collar seals released with a snap. He reached up and pulled his helm off. Light touched his skin. He breathed in…

Air filled his lungs. It had no scent or taste. It was flat, featureless – air that had never been breathed or touched life. Horkos mag-clamped the helm to his waist. The clack of ceramite on ceramite sounded briefly, and then the silence rolled back in. Horkos held still. Now that he was standing and breathing, he could feel an instinct to move rising in him. He needed to reach… somewhere. He took a step, then stopped. Where was he going? He needed a direction, and in this place he had an idea that he could walk and walk across the layer of sand and never reach anything. He did not know why, but he was certain now that he had come here deliberately. Now he needed to discover his purpose.

He closed his eyes. The stone door stood in front of his mind’s eye.

‘I am Horkos,’ he said aloud. ‘Open.’

The door opened and his mind went through.

Ahriman opened his eyes onto the plateau of dust. The past filled his mind. All of it. Every step he had taken to reach this point and place was here in his thoughts. There was no gap from being Horkos to now being himself again. In Ahriman’s mind the stone door still stood open. The persona of Horkos remained on the other side of the door, visible to Ahriman’s internal sight, a ghost shell of a person.

The plateau of grey dust, stars, sun and planets filled his physical sight. He let his mind and body settle as memories and reality reintegrated. Less time than it took to blink had passed, but at the same time a lifetime had passed. That was what it felt like.

To a mind of lesser ability, what he had just done would have been impossible to understand. It was, at least in principle, simple. To a being like Ahriman, the physical world and the mind were equally real, but while the physical world had laws and limits, the mind had none. Will, imagination and intellect were the only curbs to what a mind could make itself. Ahriman’s mind was a realm of infinite possibility. A mundane mind contained regions that it was not even conscious of, locked stores of memory, seas of emotion that hid drowned cities of desire and pain. Ahriman had long ago explored the depths of his mind and remade its landscape. He had made palaces to store his memories and walked the deserts of his subconscious. He knew himself and his mind down to the smallest grain of thought. Or at least that was what he believed. His mind was a world that he could move through at will.

Once, his mental landscape had taken the form of a palace, but that structure had fallen, its ruins standing on a headland above a grey sea, its stones looted to make temples and castles in other regions of thought. Great cities now grew out of mountains, and climbed to the sky, spans of imagined bridges and steps leaping up and up impossibly to spread across the underside of clouds. Roads crossed plains of trees that shifted under the fall of rain and then plunged down into buried warrens where there was no light, and the only sound was the drip of water growing stalactites as it seeped from the layers above. Its features were pieces of real places. A spire’s staircase might have come from the Imperial Palace in the time of the Great Crusade, but now its steps twisted around the inside of a tower that Ahriman remembered from burnt Prospero. The smell of cinder blossom on the wind blowing through a window could be a memory of the air on Damertan but with a hint of rain from a storm on Terra. On and on it went, the land growing and changing as Ahriman’s mind expanded.

Every part of this memory realm held meaning. In stone libraries were the names and lives of everyone that he had seen die. Half-buried in the dust of a desert were basalt slabs carved with the beliefs he had held when he had been a warrior newly raised to the Legion. Here Ahriman could find memories long buried, gain insight from the past, or retreat to do great work in the safest and most private place possible. It was his mind kingdom, his sanctuary, his fastness, and his store of thought.

The black door in Horkos’ thoughts had been a portal back into Ahriman’s memory realm. The whole of Horkos’ being had been a single closed room in Ahriman’s mind. While the door remained closed, Horkos had lived, and Ahriman had been just a memory hidden out of sight. Now Horkos returned to his place, another idea locked away in Ahriman’s mind. It had been a way of hiding, of vanishing from existence.

Ahriman shivered. He had survived. He had arrived. His eyes and mind moved over the plain of dust, looking for any sign that he was not alone. Nothing moved or pulled at his senses. He might have arrived here first. Then again, even if he had not, would this place show any sign of another presence? He had an idea that it might not, that no matter how many reached this shoreline of time and reality, each of them would always be alone. So far to come and stand here… So far and with so much lost. Ignis, Astraeos, Ctesias, Sanakht, Amon… all the rest. So many. So far to come. Now just a little further.

And what if you fail now, Ahriman? said a voice in his thoughts that might have been his own or might have been any of his lost brothers’. What then?

‘Time to go,’ he said to himself.

He turned away from the sun. He looked directly forwards. Nothing moved. He took a step. Nothing changed. The position of every star was the same as it had been before he had taken the step, but somehow he was facing the sun again. He knew that if he took a thousand more steps and turned in every direction, the stars and planets would be in the same position, and the sun would always be directly ahead. He drew breath and let his eyes see truly.

The sun was black. Suddenly and completely. There were no stars and no planets, just a great echoing absence all around. The plateau of dust glowed, the underside of every grain of sand lit with a green light. Deep in his skull Ahriman felt a scream rise, the scream of a living thing that suddenly saw that everything it knew and cared for meant nothing and would mean nothing. Old, human instincts shouted at Ahriman to look away, to not see this. He kept his mind still, and his eyes open and unblinking.

He began to walk. The plain of grey sand bulged down under his tread, forming a conical depression. The sides became steeper and steeper. The bottom of the depression burst into the darkness below. Ahriman was half running, half falling now as a black abyss opened in front of him and beneath him. The sand was falling past him, draining down into the well mouth. The shout in his skull was a shriek of warning. Then he was not running but falling and falling without end.

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A BLACK LIBRARY PUBLICATION

First published in Great Britain in 2024.
This eBook edition published in 2024 by Black Library, Games Workshop Ltd, Willow Road, Nottingham, NG7 2WS, UK.

Represented by: Games Workshop Limited – Irish branch, Unit 3, Lower Liffey Street, Dublin 1, D01 K199, Ireland.

Produced by Games Workshop in Nottingham.
Cover illustration by Dan Watson.

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