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The Oath in Darkness - David Annandale

About the Author

An Extract from ‘Blackstone Fortress’

A Black Library Publication

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The Oath in Darkness

David Annandale

‘Do you think she knows what she’s doing?’ Lorn Rekkendus asked.

‘It’s a bit late to be wondering that, isn’t it?’ said Harant Dalkan.

‘That is not an answer.’ Lorn was not going to be put off by Dalkan’s deflection. He couldn’t blame her. He had been asking himself the same question. It had become far more urgent since they had all arrived at Precipice. The plan, which had seemed a glorious crusade in the abstract, a mission commanded by holy visions, looked like an act of madness now that they were actually in orbit over the Blackstone Fortress. The reality of the thing was far beyond any conception of it. No one should speak of the Blackstone Fortress without having seen it. Dalkan regretted that he had come to this understanding too late.

They were in Dalkan’s prayer cell aboard the Sanctified Journey, the Rekkendus yacht moored to Precipice. He had prayed more than usual for the Emperor’s guidance since arriving. If he had known its true nature before coming, Dalkan wondered, would he have agreed to Buria’s plan at all? Precipice was a foul place. It was beyond heretical. Humans and xenos coexisted in a cauldron of competing agendas. The clamour of trade, scheming and conflict was overwhelming. It was even louder to the ear of the soul. Every breath Dalkan took here felt like an offence against the Emperor.

Did Buria Rekkendus know what she was doing? Dalkan wished he knew.

‘I believe she does,’ he said to Lorn.

Buria’s younger sister frowned. She saw through to his camouflaged doubt as surely as if she had pierced him with her third eye. ‘I am not young,’ she said. ‘I have not been for quite some time. I know very well that when I hear someone assert something by saying I believe, then they are trying to convince themselves of the truth of that statement at least as much as they are trying to convince me.’

Dalkan was silent for a moment, acknowledging the truth of her accusation. Then he said, ‘I have believed in your sister’s judgement for as long as I have been confessor to your house. I have never had any reason to doubt that judgement before.’

This was true. Rekkendus was a proud house of the Navis Nobilite. The service of its Navigators to the Imperium had been exemplary for centuries. Buria’s reign at the head of the family had been singularly successful. It was marked by a combination of rigorous discipline and a willingness to take brave risks in the name of the house and of the Emperor.

‘This is not the first time Buria has taken a radical initiative,’ Dalkan said. ‘She has always been right in the past.’

‘She has,’ Lorn agreed. ‘That is why I have gone along with her plan this far. But she has never attempted anything quite like this.’

‘We knew that before coming here. You knew that before coming here.’

Lorn nodded. ‘But we have yet to do anything irrevocable. We can still turn back. We haven’t yet descended to the Blackstone Fortress. But she has gone now to meet with our guide. The point of no return is fast approaching.’

‘Have you spoken to Viktur about this?’

‘Delicately.’

That went without saying. Buria’s son was impulsive, and he lost his temper easily. He had a habit of making fraught situations worse than they needed to be.

‘His view has not changed,’ Lorn went on. ‘His only concern is that our house achieve ascendancy over House Locarno. He would likely be here even without my sister’s visions.’

Buria was the most powerful Navigator of the three. Her connections with the warp were profound, and Dalkan worried about the long term. House Rekkendus could ill afford to lose her. Viktur was not fit to lead yet, and Lorn was too cautious. Buria spoke and prayed with Dalkan every day. He watched over her spiritual health. It was her physical well-being that worried him. But it was the depth to which she could interface with the warp that had led to the revelations she had experienced, and that had brought them to the Blackstone Fortress. Within the monster, there was a ship. Buria did not know its name or its precise provenance. It was a Navigator’s vessel, though. That, she knew beyond any doubt. It called to her. It shone, it pulsed, it sang with the power of the artefacts within. Something of enormous value to the Navis Nobilite had been lost an age ago.

Finding the ship and salvaging what lay within would be a colossal victory. It would be a triumph for the house. Dalkan didn’t think Viktur could see much further than that. But to seize something so powerful that it reached across the void to Buria, even from within so dark and malevolent a prison, would mean extraordinary things could be done for the Imperium.

Buria understood that. If Dalkan could help in any way in the recovery, it was his duty to do so. Buria had made it very clear she did not expect him to come on this mission.

But I must, he had told her. If you go and do not return, I will have to live wondering if there was anything I could have done to help.

‘So we are committed, then,’ said Lorn.

‘I am.’

‘Then so am I.’

They left Dalkan’s cell. They walked down the passageway that led from it to the observation chamber. There, Viktur was leaning against a bulkhead, looking out of the viewport. Docking tubes stretched out from the hull of the station, spiking in every direction. Most held ships, tethering them in a precarious embrace above the Blackstone Fortress’ gravity well. Below, the triangular end of a colossal arm of the fortress loomed in from the left, filling half the viewport.

Dalkan did not like to look at it. Yet when he was in this room, he could not tear his eyes from the huge, angular darkness that hid the stars. What looked like small blocks on the surface of the fortress were masses a hundred feet high and more. The construct was, Dalkan thought, the very embodiment of the concept of fortress, but even there, the word was inadequate. As impregnable as the structure appeared, it would be a terrible mistake to view it simply in defensive terms. Aggression was built into every crenellation, every rampart, every wall, and most of all in the monstrous black pyramid at its centre, the pyramid Dalkan was grateful he could not see from this perspective.

‘How long has mother been gone?’ Viktur asked. He had been absent himself. He had a black eye, his knuckles were red, and he looked very pleased with himself. Since arriving, he had been spending his time in Precipice’s drinking holes, looking for fights. Even those, from his perspective, served the family name.

‘A while,’ said Lorn. ‘She’ll be back with our guide.’

‘At last. Time we were about this.’

Dalkan disapproved of the way Viktur looked at the fortress. ‘Beware your hunger,’ he said. ‘If it is not a desire to serve the Emperor, it is the hunger of pride.’

Viktur shrugged. He was tall, like his mother, and shared the sharp, hard planes of her face. His blond hair was shaved on the sides, and he kept a lustrous tousling down on his crown. His beard was a small, groomed point on his chin. A headband of embroidered silk covered his Navigator’s eye, and was the only sign he bore as yet of any kind of mutation. He was the conscious projection of Navis Nobilite aristocracy.

Lorn was quite a bit shorter, though still taller than Dalkan. Viktur was holding on to his youth, trying to deny the inevitable transformations that came for Navigators. She had accepted hers. Her robes, though lightweight, seemed to weigh her down. She did not always need the cane she carried, but she did not dare go far without it. Her shoulder-length hair was grey, and her eyes were shadowed with experience and caution.

‘Take heed,’ Dalkan tried again with Viktur. It was worrying that he was already so consumed by the promise of power to be found in the Blackstone Fortress. They were going to an evil place. If Precipice was already a moral cesspool, what awaited over in the fortress was something Dalkan didn’t want to imagine. ‘Do not let yourself be corrupted by what lies below.’

‘We shouldn’t be corrupted by cowardice either,’ Viktur snapped.

Before Dalkan could respond, the door to the quarters slid open and Buria entered. She was the most powerful Navigator in House Rekkendus, and her affinity for the warp had taken a heavy physical toll. She had fought against it with juvenat treatments, and had the taut look of coiled wire. An augmetic framework attached to her limbs gave her strength and mobility very close to that of her youth.

Behind Buria came the guide. Dalkan’s jaw dropped open, aghast.

‘This is Dahyak Grekh,’ Buria announced. ‘He will take us where we need to go.’

‘Mother,’ said Viktur. ‘Are you mad?’

For the first time in years, Dalkan found himself in perfect accord with Viktur. The guide was a xenos horror, a kroot. His bipedal shape was a mockery of the purity of the human form. He was beaked, though his scaled hide was reptilian rather than avian. He carried a long, bladed rifle, and had to duck to get through the doorway. He looked at the humans before him. The bird beak snapped with sharp clicks.

An inhuman voice said, ‘Soft… klik. Soft and weak. Easily broken. Do well and remember this. You are foolish to be here… klik. Less foolish to hire me.’

The humans were as weak as their payment was good. It was good that Grekh’s oath was strong, or snip-snap, the Blackstone Fortress would cut them down.

He eyed them one at a time, seeing what he needed to know. He marked them as his herd, and looked for the weakest among the weak. Easily done. The priest, Dalkan. He was not a fighter. A worthless prey, no value at all in him. He was stupid to have come. He would contribute nothing.

Worse than nothing. Dalkan radiated disgust and anger. Hostility to the guide, a bad start. Viktur was as bad. At least Buria, the contract holder, was not hostile. Nor was Lorn, accepting her egg-mate’s decision to hire Grekh. And Buria’s will was clearly strong. She had a clear mission below, a good sense of what she was seeking and why. That would help. Lorn and Dalkan showed commitment to her too, another bit of good news. Viktur seemed less focused on Buria, more on himself. He would need to be watched. His judgement would be bad.

Lorn, Viktur and Dalkan were staring at Grekh. He was used to this. All human interactions began this way. Best they got their staring done before the descent to the Blackstone Fortress.

‘We go then?’ said Grekh. ‘My ship is ready. The Blackstone is always ready. Are you ready? Yes or never. Decide now... klik.’

Viktur was shaking his head. More stupidity. This was not his decision. He had not listened. He was posturing. So much posturing. Humans never tired of it. Wait it out.

‘I will not have our name soiled by associating with xenos filth,’ Viktur said. ‘Find another guide, mother. Or I will.’

‘There must be another way.’ Dalkan took a step further back from Grekh. He smelled of frightened prey. He was trying to decide whether to attack or fear being eaten.

He was safe. Grekh was under contract. And there was nothing to learn from the priest’s flesh.

‘There is no other way.’ Buria’s words were an edict. She raised a hand. The mechanism on her arm gave the gesture imposing strength and she silenced the others. Good. Good. ‘This kroot has been to the fortress more often, and has gone deeper, than any human guide.’ She rounded on Viktur. ‘You may go by other means if you like. If you wish to die.’ Her voice was hard, commanding hard. All very good.

‘Yes or never?’ Grekh asked. For the last time.

It was yes.

A metallic scrape, and a change in the feel of the station, something deeper than a vibration but akin to it, that Grekh sensed more than felt. Two threats, immediate and imminent.

Grekh held up a hand. The Rekkendus party stopped immediately. Even Viktur was behaving with discipline for the moment.

They were moving down a long hall. Its walls sloped away from the floor at a steep angle. The deck was about fifteen feet wide. The walls went up and up, opening wider and wider. The ceiling was invisible in the dark heights, but from it hung structures that resembled gigantic, squared-off stalactites. At their ends, each was as wide as the corridor. There were rows and columns of them, and they moved with slow, clockwork regularity. With a heavy, grinding shift, the masses exchanged places, creating new patterns. Grekh had yet to find any reason for the movements and the configurations. They were a slumbering machine’s dreaming stirrings.

There were deep alcoves at apparently random intervals in the hall. The inverted pyramids glowed a faint red, providing just enough illumination to see by, but the alcoves had their own, low ceilings, and were filled with profound shadow. Grekh pointed, wordlessly ordering his herd into the nearest one. He pushed the humans back towards the wall, more than ten feet away from the hall. He waited near the front, invisible from the corridor, but close enough to the mouth of the alcove to see what approached.

Spindle drones passed, their movements a scuttle and a float as they were propelled by their three insectile legs. Their cyclopean eyes scanned forwards, and they ignored the alcove.

Silence fell. Grekh did not move from his position. The second threat was still growing.

‘What are we waiting for?’ Viktur hissed. ‘They’re gone?’ He pushed forwards.

Grekh shoved him back. Viktur kept trying to assert authority. He made noises about wanting to lead the party, even though he did not know where they were going, or what he was doing. It was all just more posturing. Grekh had no patience for him.

‘How dare you touch me?’ Viktur said. ‘I’ll have your head.’

‘Do be quiet,’ said Buria.

Grekh said nothing. If Viktur wanted to forge on ahead, abandon the party and remove himself from the shield of Grekh’s oath, then let him do it. Grekh would be happy to let him become the fortress’ prey. Much as he felt contempt for the human, though, Grekh had no wish to eat him. It would be bad meat, and full of lies.

At least Viktur was stopping short of putting Grekh in the position of having to decide what the oath commanded – not harming any of party at the possible cost of losing them all, or killing one to save the rest.

So far, the advance into the Blackstone Fortress was going well. They had avoided any skirmishes. When Grekh was on his own, the right kills could add to his knowledge of the structure. But when he was a guide, a successful mission was going in and out without disturbing the sleep of the great beast.

‘Why can’t we go?’ Viktur insisted.

‘Change,’ Grekh hissed. This was not something he should still have to explain.

Dalkan understood. The priest moaned in fear. He was proving to be a different kind of problem. His muttered prayers had become more and more intense the further the party ventured into the fortress. Grekh wasn’t sure how much more the priest’s mind would be able to take. He was living a nightmare. That wasn’t good when one could not wake.

The changes that convulsed the interior of the fortress had already happened a few times. Each time, Dalkan’s reality crumbled badly. But he was still mobile. He was not mad yet. He had done nothing to take him outside of Grekh’s protection, whether the priest wanted it or not.

The change came. The corridor stretched wide, the opposite walls receding rapidly from the alcove. The great stalactites locked into their current positions, and then descended. Lorn clapped a hand over Dalkan’s mouth, muffling his wail. The colossal shapes came down like closing jaws. At the same time, the alcove rose. It passed the dropping stalactites fast enough to generate a violent gust of wind. The teeth almost ground together. For several moments, Grekh and his herd could see nothing but the crimson glow of the masses. Then the alcove jerked to a halt that knocked Dalkan to his knees.

Where before the change the party had been moving through a long, narrow cavern, now Grekh looked upon a plateau. The ceiling was still invisible, concealed in blackness. The walls had vanished too. The stalactites had detached from the ceiling. Their bases formed broad surfaces separated by zigzag patterns of crevasses. There was still the red glow, and the gaps between surfaces were only a foot or so across. A careful leap, Grekh judged, was within the capabilities of every member of the herd.

The question was the direction to take. They had risen at least a hundred feet in the last few seconds. The landscape had changed.

Grekh turned to Buria. He had never seen what she had come to find. As long as she had a direction to go, he could take them down that road. This was the largest alteration of the fortress’ interior they had yet encountered, but Buria did not hesitate.

‘There,’ she said, pointing.

There was no port or starboard, bow or stern inside the Blackstone Fortress. For Grekh, there was in, and there was out. Buria needed him to take her further in.

He obeyed.

They moved through the vastness of the chamber. They all felt exposed, but Grekh kept the pace steady and careful. Any of his herd that rushed would die. He made his charges pause at the edge of every crevasse, and focus entirely on their leap. It took half an hour before they finally saw another wall. It had a doorway canted at a strange angle.

During the crossing, Grekh became uneasy. The fortress had not quieted as he had expected after the last upheaval. The sub-sensory hum continued. There was more change coming, and he couldn’t tell how close it would be, or when it would occur. The forces that were triggering his instincts were too vague. Or they were too broad.

He entered the corridor, moving more and more cautiously. Something was wrong.

The hall was a tube. Its sides were scored, creating a tight spiral that ran its entire length. The ridges looked both like grilles and tendons.

Now it was Buria who tried to push past Grekh. He held out an arm to stop her. ‘Be wary,’ he said.

‘But we’re close,’ she breathed, eyes shining.

‘Then we should have more caution. Not less.’

‘Listen to him,’ Lorn pleaded. ‘We can’t be foolish, especially if we are so close to our goal.’

Reluctantly, Buria took a step back.

The tunnel curved around sharp bends. Branches opened up. Buria chose the left branch at the second intersection, and then ignored all the other tunnels that led off the new route.

Grekh stopped. He gave his head a quick, hard shake. ‘We head back,’ he said. His instincts were screaming at him. Something was coming, something he could not protect his herd from.

‘No!’ said Buria. ‘We’re almost there. We go on.’

‘Back,’ Grekh insisted. ‘Off the fortress.’ Premonition hit him like a blow, his entire body reacting to the imminence of disaster. This was a new thing, new and terrible. He had never encountered its like on the Blackstone Fortress. He had no strategies for it. No one could. Whatever was coming was too big. He felt it building up like a wave a thousand feet high, and it was about to crash down and destroy them all.

‘Coward!’ Viktur snarled. He shoved past Grekh with his mother.

Staggered by the sense of onrushing vastness, Grekh was too slow to respond. He reached for Viktur’s arm as if he were moving underwater. Then the bond of his oath snapped him back into action.

‘Come back!’ Dalkan shouted behind him as he started after the Navigators.

Grekh did not know if the priest was calling him or Buria.

It did not matter. The tunnel split in two. The decking on which Grekh stood heaved upwards. Dalkan, Lorn and Grekh fell as the floor shot upwards and its angle approached the vertical. They grabbed hold of the ridges and clung to a deck becoming a wall.

The tunnel opened up like the pincers of a crab, and it became just a ridge in a gargantuan chamber. Dalkan was screaming, but Grekh could not hear him. The change had come. It was tectonic in scale, and had the violence of an eruption. The enormous machinery of the Blackstone Fortress’ being roared to life as it never had in all the time of Grekh’s exploration.

For several long minutes, he could see nothing. He had only the impression of colossal movement, of mountains rising and falling, and of something gathering, a centre forming. This was willed. This was change with a purpose.

Dalkan’s grip slipped. Grekh reached down and caught his wrist just as the priest began to fall. His rifle slung over his shoulder, his muscles straining, Grekh held himself and Dalkan in place with one hand. Lorn held fiercely to the wall beside them. She had lost her cane, her face was red with strain, and her fingers were white. If she fell, Grekh would have to drop the priest, who was not a Rekkendus.

He did not want that to happen. He disliked thinning a herd in his care.

Grekh stared into the violence of the change, and he saw the centre that was taking hold. He saw walls with a recognisable function. He saw jagged spires and turrets of blackstone. A twisted citadel within a fortress came into being before him. Warp-fire leapt from peak to peak, and auroras of madness billowed from its windows.

At last, the transformation ended. Grekh crawled to the peak of the slope, dragging Dalkan with him, then went back down to help Lorn to safety. On the platform they reached, they looked out at the high, grim walls and glowering parapets of the citadel.

‘What does this mean?’ Dalkan whispered.

Grekh knew Dalkan was not speaking to him. The priest was crying out to his god. Grekh answered all the same. ‘It is the work of an enemy. One we are not prepared to fight. The Rekkendus path ends here.’

As towering as the citadel was, its vista swept off to both sides as far as Grekh could see. This was not an obstacle they could get around.

‘Where are the others?’ Lorn asked, voice shaking with pain and exhaustion.

‘To be found klik,’ said Grekh. He knew where Buria and Viktur had last been. He had to discern not their movements, but those of the fortress’ interior landscape. Where the section of floor he had been on had risen, the other had dropped. He had the scent of the two humans. He could track them through a maze.

Grekh stood and moved to the other side of the platform. He eyed the downward slopes and curves of the reconfigured structure. He found the traces of motion in the new shapes. He saw where a tunnel had gone to become a wall, and how a wall had joined others to become a spire. He saw where a tower had grown, and how a parapet had come to be.

He saw where Buria and Viktur had to be.

‘They are there,’ he said, pointing at the base of the citadel. Just above its roots was a small bulge in the outer wall of one of the towers. ‘Inside.’

It was not far, in real distances. If the fortress remained still, that is – and Grekh felt it would; that in this region, at least, whatever forces had created this citadel would be satisfied for now.

That was what concerned him. The enemy that had done this was formidable. More than the interior of the Blackstone Fortress had changed. Something fundamental had altered.

There was no room to contemplate consequences now, but Grekh felt them looming as high as the citadel’s walls.

‘Follow close klik,’ he said. There was a ridge that sloped down from their position towards the base of the citadel. Taking it would expose them to what sentinels might be in those walls. It was also the only way forward.

Grekh unshouldered his rifle and took the ridge, moving as quickly as he could without leaving Lorn and Dalkan behind. Lorn was unsteady without her cane, but she kept up with the priest, urgency granting her speed.

They reached the bottom of the slope without being attacked, and crossed the wide stretch of deck to arrive at the tower. There was an open doorway in the curved outer wall, and inside the deck headed up again. Buria and Viktur’s scent was strong. The contract holder was not far.

Grekh paused at the doorway. Foul ichor dripped from the walls and ran in channels down the deck, carrying the stench of nightmares and monstrous fates. There were other scents, too, enemy ones. They were pervasive. He couldn’t localise them. It was as if they were part of the very fabric of the citadel.

Bad signs. No resistance was a bad sign too. And he had no choice.

He climbed, the other half of his herd behind him. Dalkan was sticking close, his revulsion for the kroot overcome by his fear of his surroundings. Lorn was right behind, frantic to find her sister.

The deck wound up inside the tower twice, and then the entrance to the bulge appeared, another angular doorway, savage in its shape, as if its edges were razors. Voices emerged, Buria and Viktur speaking with muted intensity.

‘I don’t understand!’ Viktur was saying. ‘Why won’t you tell me what is happening?’

‘Soon. All is well.’

‘But…’

‘All is well. We’ll wait a bit longer. We always knew there was a chance not all of us would survive. We are still enough. Lorn is not necessary.’

Necessary? Grekh thought.

He slowed down, and Dalkan did too. But at the sound of her sister, Lorn rushed forwards. She shoved past Grekh and into the chamber.

Grekh was still a few feet from the entrance. He could see only part of the room beyond. Buria was on the left, facing Viktur, who was out of Grekh’s sight.

‘Buria!’ Lorn called, and then stopped in the middle of the room. She turned around slowly. Her eyes widened and she blanched at what she saw.

‘Threat!’ Grekh warned. He shoved Dalkan hard and the priest stumbled back down the sloping deck and fell, rolling. Grekh brought his rifle up to fire.

He wasn’t fast enough. He saved Dalkan, and he paused before pulling the trigger, because Lorn was in the direct line of fire, and that stole the fractions of a second he needed. Two massive forms stepped into the doorway, and they were already firing.

Servants of the Abyss. Corrupted Space Marines, their armour black as the fortress, the eight-pointed star of Chaos a blaze of gold on their pauldrons. Their bolters roared in the narrow passageway, their fire an explosive hell.

They were thunder. Grekh was lightning. He jumped back and down. A slug caught him on his shoulder plate and blew the armour away. Shells slammed into the walls. The rapid-fire hammer of explosions became a single blast, and then the walls were coming down on him, and with them darkness.

The battle was over before Dalkan had finished falling down the ramp. A portion of the inner tower wall fell on Grekh, and there were a few moments of silence. Smoke filled the twisting corridor, and Dalkan lay still. He waited for death, and prayed to the Emperor that he would meet it with more dignity than he had the horrors he had witnessed so far in this corrupt nightmare of a place.

He heard voices. Lorn’s first, shouting in incomprehension.

Then Buria spoke, sounding horribly calm. ‘We don’t need him any longer. Let’s go.’

‘What are you saying? By the Throne, what are you doing?’

‘Don’t question me. Viktur, are you ready?’

‘What? No, mother. This is wrong.’

Dalkan had never heard Viktur stand on principle before. He had never heard him sound so frightened either.

‘Take them,’ said Buria.

There were sounds of scuffling, and then the heavy tread of ceramite boots, heading higher up the tower.

‘Is it far?’ Buria asked.

‘Close enough,’ said a voice, deep and harsh through a helmet’s vox-speaker.

The footsteps receded. Dalkan got to his feet and staggered back up until he was level with the rubble. The collapsed wall covered most of the corridor, but there was still room to clamber over it and follow.

To what end? What can I do?

Nothing. You useless, useless fool.

He was going to die here, and die for nothing. He had believed in a traitor.

The rubble stirred slightly. Dalkan heard a grunt of effort.

By the grace of the Emperor, the xenos monster was still alive. The kroot was an offence merely to gaze upon, and he was also Dalkan’s only source of hope. There was only one living being who could be the hand of the Emperor here and now.

A gigantic theological problem unveiled itself before Dalkan. He prayed that he would live to contemplate it.

He pulled at the wreckage, shoving off the fragments small enough for him to shift. ‘I am here,’ he whispered fiercely, as if he were the one giving comfort. ‘I am here.’

‘Quiet and dig,’ the inhuman voice snapped.

Dalkan worked at the rubble. It sliced his hands. It felt like it was biting him. It was something that looked like stone, but only, he thought, because it chose to do so. In another few seconds, it might flow into another change, crushing Grekh out of existence.

The top of the rubble loosened. Dalkan heaved a slab off. The kroot found leverage, and fought his way out, bleeding and furious. He paused to check his rifle, then opened a small canister in the pouch of his belt. From it he extracted a thick, bloody paste that he smeared on the bleeding, burned flesh of his shoulder. He snapped his beak with a sharp, satisfied click.

‘What must we do?’ Dalkan asked. He heard the deference in his voice. Only a tiny, irrelevant part of his consciousness thought it was strange.

‘Buria Rekkendus has broken the contract. Our oath does not bind us to her any longer.’

‘Lorn did not betray you. Nor did Viktur.’

‘No. The oath holds for them. Also for you.’

‘Save us.’

‘I will.’

If he had been tracking the Servants of the Abyss, Grekh would have found the hunt challenging. Theirs was the scent that filled the citadel. This was their doing, somehow. They had grown in strength. They had become terrible in their threat, and he was in their stronghold.

The Rekkendus scent, though, was easy to follow. Buria and the Servants of the Abyss had taken the others higher in the tower, and then down a long, narrow passage. It was barely large enough for a Space Marine to pass through, and its nature gradually changed as Grekh and Dalkan made their way down its length. The matter of the Blackstone Fortress mixed with metal alloys of human construction. The tunnel was a ship’s conduit that had been fused with the fortress.

Grekh took the last few yards of the tunnel slowly, dropping down to a crawl and signalling to Dalkan to stay back. The conduit was dark, giving him the cover of shadows as he looked into the circular chamber beyond.

This too was part of a ship, or had been. It was an ancient bridge, and had long ago become one with the Blackstone Fortress. Buria had been telling the truth about the existence of the vessel. She had either been lying or was deceived about the possibility of extracting it from the fortress.

Objects rose from the deck that had the shape of control surfaces, but had become tumour-like extrusions of the fortress’ matter. A fissure midway up the walls ran the entire circumference of the bridge. It opened and closed, a lipless maw revealing rows of fangs. In the centre of the deck sat what was still recognisable as a command throne, though its shape had a fluidity no human, kroot or t’au construct had ever had. It was linked by writhing, viscous mechadendrites to two other thrones. They were half-sunken in the floor, or perhaps they had half-emerged. The changes to the ship were so profound that there was no distinguishing between the features that were echoes of what it had once been, and those that were the marks of what it had become.

Buria stood beside the central throne. Lorn and Viktur were in the other two, and the seats had partly closed over them like cocoons. A squad of Traitor Space Marines surrounded the thrones, watching.

‘Mother!’ Viktur shouted. There was no bravado in him now. Only fear. ‘What are you doing?’

‘Ascending,’ said Buria. ‘You have always been a disappointment to me, Viktur, but at least you will be useful. Your ability and Lorn’s will be slaved to mine, and I will pilot the greatest weapon the galaxy has ever seen.’

‘Then do it,’ said the commander of the Traitor Space Marines. ‘You can gloat later.’

‘We will fight you,’ Lorn vowed.

‘You can’t,’ Buria said with a smile. She gave the Servant of the Abyss a regal nod, and climbed into the throne.

Grekh looked over the sights of his rifle. He might be able to down one of the Space Marines. He had a clear shot into the warrior’s helm lenses.

Not good enough.

He would kill one enemy, and then die, having saved no one, and broken his oath.

Mechadendrites slithered around Buria’s arms and chest. Her smile faltered. ‘What…’ she began. She started to twitch.

‘You will pilot nothing,’ the commander snarled at her. ‘The three of you will be a single force at the command of Obsidius Mallex. Through you, he will wake the fortress. He will guide its path of destruction.’

All three Navigators screamed. Their third eyes opened. A psychic wave rippled through the chamber as minds began to fuse and identities began to melt. The thrones glowed, and a hemisphere of roiling warp light slowly expanded from their centre.

Grekh felt something very deep, and very great, stir in the heart of the Blackstone Fortress, and now he saw how he could fulfil his oath. He could still save his herd.

He fired three times, placing every shot in the warp eye of one of the Navigators.

As she died, Grekh thought he saw a look of gratitude on Lorn’s face.

The Space Marines turned in his direction, bolters rising.

The psychic build-up imploded. The bodies of the Navigators collapsed on themselves, and the thrones followed. An instant later, the warp energy erupted again, lashing out uncontrollably, devouring the chamber and the Servants of the Abyss.

Grekh spun and ran. The pain of his injuries tried to slow him, but his will and his oath were stronger than agony. Grabbing Dalkan, he sprinted back down the conduit, and then towards the base of the tower. The eruption grew in power. The walls and deck shuddered, and a sound that was both thunder and shriek rocked the tower.

Dalkan ran fast, doing well for the weak thing he was, and when they reached the base of the tower and fled the citadel, Grekh knew he would save this one also. The destruction he had caused would buy them time. He would carry the priest if he had to, but he would see this one alive back to Precipice.

They had to reach Precipice, because he would have to make a new oath. His old reasons for coming to the Blackstone Fortress had died with the birth of the citadel. So had those of every living being on the station.

Whether they knew it or not, they were now at war.

About the Author

David Annandale is the author of the Warhammer Horror novel The House of Night and Chain and the novella The Faith and the Flesh, which features in the portmanteau The Wicked and the Damned. His work for the Horus Heresy range includes the novels Ruinstorm and The Damnation of Pythos, and the Primarchs novels Roboute Guilliman: Lord of Ultramar and Vulkan: Lord of Drakes. For Warhammer 40,000 he has written Warlord: Fury of the God-Machine, the Yarrick series, and several stories involving the Grey Knights, as well as titles for The Beast Arises and the Space Marine Battles series. For Warhammer Age of Sigmar he has written Neferata: Mortarch of Blood and Neferata: The Dominion of Bones. David lectures at a Canadian university, on subjects ranging from English literature to horror films and video games.

An extract from Blackstone Fortress.

How they would have wept to hear him. All those years of brutal tutelage, so many prayers meted out with an unsparing stick, and not one of their aphorisms had stayed with him – all that cant wiped away by the savagery of the war. Only one simple phrase, whispered to the rhythm of his breath, had kept him alive. Through the needle’s eye. He could see it in his mind – a sliver of sanity, surrounded by a galaxy of madness. I live or die.

In place of a sky, it seemed Sepus Prime wore a dirty, sodden cloth, stained the same feculent shade of dun as the mud below. It sagged low over the fly-clad marshes, bleeding a desolate rain, crushing the mounds of dead and billowing around a shame-faced sun. Glutt waded through the filth, a slight man weighed down by a heavy coat. His face was a mask of dark, viscous mud, and his mouth was hidden by a rebreather. Only his eyes were visible – flashes of white beneath a peaked cap, scouring the trench for the shot that would finally kill him.

‘Through the needle’s eye,’ he whispered, risking a glimpse into no-man’s-land, using his staff to haul himself over a broken trench wall.

Fumes lay heavy on the swamp, crawling lazily over shattered gun emplacements and crook-backed trees. Even through his rebreather Glutt could smell the chemical stink of enemy weapons. How many of the regiment were still alive out there? Betrayed. Clawing at their throats, calling for loved ones, begging for the help they were promised. The reinforcements that never came. They never came. They had all been fools, but he would be a fool no more. Anger fractured Glutt’s thoughts, dangerous and raw. He recited his mantra with vehemence, clinging to his mind, weighing it down with words.

He pulled out a map and wiped it clean, tracing a finger over the gridlines, counting the miles. He was close. Another few hours and he would see the barracks. He had no desire to rejoin the regiment now, after all that he had seen, but where else could he go? He had no vox and he dared not risk any other method of communication, and this side of the valley seemed to have been forgotten. The earth shivered beneath a mortar shell rain, but it was a distant sound, like the echo of a storm.

An image flashed through his mind, so vivid he gasped – pale, ruptured flesh tearing over a clinker-black shell. He drove the vision down but it coiled beneath his thoughts, waiting for his guard to slip. He had seen it countless times over the last few months. It was horrific, but part of him was also fascinated. It was so clear. What did it mean?

He was about to drop back down into the trench when he saw movement in the smoke – half a mile away, near a bombed-out gun emplacement. He grabbed his laspistol and peered through the scope.

‘Sorov?’ he whispered, catching a glimpse of red sash.

There was another blur of movement, then nothing. Only the lolling, yellow fumes and the sporadic grumble of mortars. He had not seen a soul for two days. Perhaps he imagined the shapes? Then he heard a faint crackling – not the rattle of gunfire, but the white noise of a vox-unit. It came from the gun emplacement.

He dropped into the bunker, his breath coming in snatched bursts. Insurrectionists were everywhere. Snipers haunted every gully, masquerading as corpses, lying patiently beneath cold limbs, waiting for some fool to break cover. Again he heard the crackle of vox traffic, muted by the fumes but unmistakable.

He peered up over the scorched embrasure, looking through the gunsight again, trying to guess where a sniper might hide. There was a rusted tank chassis, halfway to the gun emplacement, jutting from the mud like an unearthed fossil: a Leman Russ, one of its sponsons still visible, pointing defiantly at the leaden clouds. Just the kind of place a sniper might wait. He looked in the other direction. There was a trench, parallel with his, about a hundred feet away. It had caved in, sporting a crest of broken joists and blast-warped girders. Again, exactly the kind of place snipers might hide. There were cadavers in the razorwire, swaying in the breeze like abandoned marionettes. It looked as though they had been thrown clear of the trench by an air strike, but he had seen traitors adopt that pose, then lurch into movement at the first sign of a target.

‘Lieutenant Sorov?’ he whispered. Could he still be alive? And if he was, why would he be here? The push on the civitate had started. Sorov always led from the front. Why would he be back here, so far from the front line? The thought that the lieutenant might still be alive shook Glutt’s resolve. Sorov had stood by the men. He alone in all the regiment seemed worthy of trust.

Glutt hunkered in the trench, crippled by indecision. The image of torn flesh washed through his thoughts again, but he crushed it with his mantra, determined to think clearly. What if it was Sorov out there? Could there still be another route for him, even now?

Glutt bolted up the trench wall and ran through the smoke, head down, flicking his pistol from the tank to the corpses. His footfalls rang out through the smog. Slap. Slap. Slap. Flies whirled around him, drawn by his blood-black coat. Sweat pooled in his eyes. He tried to sprint, but his legs were wasted from lack of food and the mud gripped his heavy boots, leaching what little strength he had left.

Minutes passed until finally the gun emplacement reared up before him, brutal and angular, a slab of pitted rockcrete shattered by artillery. One side was intact, but the other was gone, leaving the surreal sight of a furnished room, split down the middle and hanging in the air. The furniture was undisturbed: a neatly made bunk, metal plan chests, a small dining table; all perched in the clouds, washed clean by the endless rain.

Glutt had almost reached the walls when he heard someone snap the safety off a lasgun.

He staggered to a halt, his heart thudding as he tried to pinpoint the sound.

‘The savant?’ The words were spoken quietly, but they echoed across the swamp, eerie and dislocated.

‘Lieutenant Sorov?’ gasped Glutt, still crouched, staring at the shifting clouds.

‘Throne,’ said Sorov, striding into view, flanked by Guardsmen, their lasguns trained on Glutt.

‘In,’ he snapped, waving for Glutt to approach.

Glutt staggered forwards, into the arms of the Guardsmen, who grabbed his filthy coat and hurled him inside the ruined tower.

As Glutt lay panting on the floor, Sorov and the others stood over him, scowling.

Sepus Prime could not touch Lieutenant Sorov. He shrugged it off like an idle threat. He was one of those officers with the inhuman ability to look clean, fresh and unperturbed as the galaxy went to hell around them. His hair was immaculate, oiled and gleaming beneath his cap, and the buttons on his coat flashed proudly as he moved. An old scar curved from the corner of his mouth to his ear, but even that looked deliberate – just another military honour. He studied Glutt through half-lidded eyes.

‘Where is the rest of your detail?’

‘We never made it to the front lines, lieutenant. The insurrectionists were on us before we reached Tadmor Ridge. I was able to–’ He hesitated, noting the wary expressions of the Guardsmen. ‘I was able to disable some of them, but there were too many.’

‘You’re a psyker?’

‘Yes, sir.’

‘You abandoned your men?’

‘No.’

‘They’re dead,’ said Sorov, his expression blank, ‘and you are not.’

‘I did everything I could, lieutenant.’

Sorov studied him in silence. No one helped him to his feet.

The silence was broken by the crackle of the vox-unit. There was another trooper crouched a few feet away – a comms officer, hunched over his vox-caster.

‘Ten minutes until contact,’ said the Guardsman, with the handset held to his ear. There was a tremor of excitement in his voice. ‘Everything went to plan.’

Sorov closed his eyes for a moment. When he opened them again he looked back at Glutt. ‘Tell me, Glutt,’ he said. ‘If you were a traitor, why would you have stumbled over here and revealed yourself, rather than using your talents to kill me from a safe distance?’

Glutt struggled to keep his expression neutral. Traitor. Sorov had pinpointed the doubts that had haunted him for weeks. All he saw on Sepus were pitiable fools and callous, inhuman orders. His faith was gone. What did that leave?

‘There is no reason,’ said Sorov. His expression softened. ‘You’ve done well to last this long, soldier. Not many have.’ He nodded to his men. ‘Pick him up. And keep an eye on him. He’s a sanctioned psyker. Don’t let him ruin this.’

As the Guardsmen dragged Glutt from the mud, Sorov headed over to the comms officer.

‘Korbol,’ he said, glancing up at the shattered floor of the room above their heads. ‘Anything?’

‘Nothing, lieutenant.’

Sorov nodded, and then glanced back at Glutt. ‘Over here.’

Glutt tried to brush some of the muck from his coat as he rushed after Sorov, but it had dried into a thick crust. He moved with the clumsy, awkward steps of an automaton.

‘Get me Kapek,’ said Sorov to the vox-officer.

There was another burst of static, then a voice came through the speakers, ghostly and hazed by distance, like an old recording.

‘This is Sergeant Kapek. We have–’ The voice was cut off by a series of pops and whistles. ‘We are no closer, lieutenant. Heavier losses than anticipated. The aerial strikes failed to knock out the lascannons. They’re cutting us down.’

Sorov grabbed the handset. ‘Ten minutes, sergeant.’ His voice was an urgent whisper. ‘Ten minutes more.’

There was a pause on the other end, but it was not static this time; they could all hear the sergeant breathing. ‘Ten minutes?’ he said finally, sounding shocked.

Sorov raised his voice, despite the risk of revealing himself. ‘Throw everything you have left at them for ten more minutes. It’s working. He’s headed your way.’

This time there was no pause. ‘Ten minutes, lieutenant. We’ll do it.’

Sorov looked pained and seemed on the verge of saying more, but he held it back.

‘Lieutenant,’ came the voice again. ‘Are you still there?’

‘Sergeant.’

The voice sounded defiant this time, all trace of doubt gone. ‘It was an honour, lieutenant.’

Sorov’s expression tightened. When he spoke again, his voice was as rigid as his face. ‘High command will know, sergeant. Commander Ortegal will know what happened here today.’

Another series of pops and crackles hissed through the speaker.

‘Kapek out,’ came the reply, then the line went dead.

Sorov stared at the handset for a moment. Then he took a deep breath and handed it back to the comms officer, turning to face the other men. ‘I give them five minutes, but it will suffice. By the time the insurrectionists wipe them out we’ll have hit our target.’ Sorov looked at the comms officer. ‘Federak. These are the exact coordinates?’

Federak was wiry and short, with the slabby, knocked-about face of a prize fighter. ‘This is the right emplacement, lieutenant,’ he said. ‘If Gorny got his maths right, the shuttle will pass right overhead.’

‘Good.’ Sorov looked around the group. One of the Guardsmen was carrying a rocket launcher over his shoulder. ‘If you get even one clear shot, you’ll be lucky.’

The trooper nodded. ‘Sir.’

Sorov stared at him. ‘We’ve thrown everything into this. There are a few hundred men left at the barracks, but you saw the state of them. There will be no more chances. This is it.’

The man saluted. ‘One shot will be enough, sir.’

Sorov nodded, then waved at the damaged upper floor of the tower. ‘Into position.’

He glared at the rest of the troopers. ‘Am I so pretty you can’t take your eyes off me? Watch the damned trenches. Keep yourselves alive for a few minutes and you might even get off this rancid planet.’ He caught sight of Glutt. ‘You keep out of the way.’ He leant closer, tapping the eagle-shaped head of Glutt’s staff. ‘I’m no fan of witches, sanctioned or not. Throne preserve you if I catch you trying any parlour tricks.’

Glutt saluted.

Sorov nodded to the pistol at Glutt’s belt. ‘You know how to use that thing. Join the others and watch the bunkers.’

Glutt saluted and rushed to stand beside the comms officer.

‘What are you doing out here?’ he whispered, once Sorov had climbed up into the room overhead to join the trooper with the rocket launcher.

Federak gave him a suspicious look. Glutt felt like proving his suspicions right, showing him what a psyker could really do, but he thought of the needle, biding his time. He had no clear plan. He no longer believed in the regiment, but what did he believe in?

‘The governor’s going to pass over this way,’ muttered Federak, waving his gun at the clouds. ‘He thinks he’s won. He’s racing to Tadmor Ridge to deal with Sergeant Kapek and the rest of those poor sods. Sorov got a man into his inner circle. The pilot. We know the exact route he’s taking. He’s going to pass over this spot in a few minutes.’

Glutt could not believe the lies people told themselves to try to stay sane. ‘You’re going take down the governor? What difference will that make? They’ll still massacre the rest of the regiment. The insurrectionists will still control the whole coastline. We’ve still lost.’

Federak forgot his wariness of Glutt for a moment and laughed. ‘Not destined for high command are you? Think. Before Governor Narbo took control of the insurrectionists, what were they doing?’

Glutt bit down his rage and shrugged.

‘Killing each other,’ Federak elaborated. ‘Always killing each other. Why do you think they used to be so easy to control? They all think they should be in charge. None of them will follow the others. It’s only because Governor Narbo executes his opponents that they’ve become an army. There was no insurrection until Narbo lost his mind and pulled them all under one banner.’ He nodded at the trooper with the rocket launcher. ‘We’re about to remove the glue that holds them all together.’

‘But we’ll have nothing left either.’

Federak shrugged. ‘Once Narbo dies, the insurrectionists will turn on each other. They’ll become a mess of squabbling warbands and high command will send us home with a chest-full of medals.’

‘Sorov knew this would happen,’ muttered Glutt. He looked up at the lieutenant. Maybe there was still a man worth following? Maybe he was making a mistake? No. One true man in a legion of liars was not enough.

‘Of course,’ said Federak. ‘I don’t know what Governor Narbo was smoking when he decided to join with the insurrectionists, but he should have known Sorov would never let him get away with it. The man has balls of steel.’

Glutt was about to reply when Federak frowned and looked up.

‘Hear that?’ he muttered.

There was a low, shuddering rumble drifting through the clouds – the unmistakable drone of promethium engines. Overhead, the lieutenant and the trooper with the rocket launcher shifted their position.

Everyone in the tower held their breath.

The sound grew louder as a dark smudge appeared in the mustard-yellow clouds. The lieutenant whispered something and the trooper raised his rocket launcher. The shuttle thundered right overhead – so low Glutt could see its markings.

A deafening blast rocked the tower and the sky turned white.

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A Black Library Publication

First published in the Warhammer 40,000 anthology Vaults of Obsidian in Great Britain in 2019.
This eBook edition published in 2020 by Black Library, Games Workshop Ltd, Willow Road, Nottingham, NG7 2WS, UK.

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Cover illustration by Paul Dainton.

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