The Horus Heresy: Ordo Sinister

Borealis Thoon stands alone. Silence clings to the black and bronze of its skin. Its gun arm hangs at its side, its head still between its shoulders. Had it stood in a city, it would have made avenues seem as alleys, and tall buildings as low houses. Here, though – in the labyrinth dimension of the webway beyond the Emperor’s dungeon – it seems a metal giant pausing before walking further. A half-informed observer might see it and name it a Titan, and they would be correct in part. But this is not one of the god-machines of Mars.

It is not a creature commanded by priests and raised in the image of the machine-god.

It is a Psi-Titan, and it stands apart.

The Lychway spirals away into the distance before Borealis Thoon. Through the eyes of the silent giant, the landscape resembles the inside of a conch shell. The walls are spun from twilight. Gravity follows a simple paradox here: every part of any wall is down. Every other direction is up. The humans who assign names to the webway call this the Lychway because of the pillars that line the inside of the spiral. Each of the pillars is a sharp tooth of smooth, grey ceramic. Crystal threads their substance. Voices whisper in the thoughts of those who have walked amongst them.

There are ghosts, too. Some amongst the tech-priest orders have pict-captures of willow-thin figures standing in the shadow of their servitors. Standing and watching.

Hydragyrum, master of Borealis Thoon, Fourth Initiate of the Fourth House, has seen the phantom images, but he feels nothing when he passes the pillars, and no whispers touch his thoughts. To him, the Lychway is just a place. Its pillars are silent, its ghosts absent. From his cold, iron throne, he watches and waits, just as he has for the last nine hours.

‘Surge approaching,’ says the voice of Tual over the vox, the Custodian’s words echoing inside Borealis Thoon’s skull. ‘Tide edge visible in six minutes.’

‘We hear, and awaken,’ replies Hydragyrum.

Nine hours. He has been waiting for this moment for nine hours. The time of vigil is within the value that he had derived.

He closes his eyes and draws three long breaths. He performs the action because it is ordained that he does so. He opens his eyes. In the distance, the twilight of the Lychway is curdling to crimson and black.

‘Argentis, saturnis, martias,’ he intones, and begins to slide the controls into the first set of alignments. The controls are unlike any other in any of the mundane machines of the Titan Legions. Hydragyrum’s throne sits at the centre of a sphere of steel rods. Pyramids, circles and pentagrams of gold, silver, lead, jade and bone hang from them. Apart from the cables clamped into the sockets at the base of Hydragyrum’s skull, the sphere is the sole means of controlling Borealis Thoon.

It is called the crucible.

‘Numina, kadeth, ki,’ he says, and slides the control sphere into the next order of alignments.

Beneath his throne, the three human system-governors are jerked into wakefulness. Each of them is almost a servitor, their brains cut so that alone they are just one third of a consciousness. Each of them bears the name of their function. Darkness is the first to wake. He shivers and hisses air from between his chrome teeth. The tubes burrowing into his eye sockets twitch. Hololithic projections unfold before the throne, meshing with the symbols of the crucible. Flowing runes and images cast new shadows across Hydragyrum’s face.

‘Tide visible in one minute,’ says Tual. ‘I hope you are ready.’

Hydragyrum does not reply.

‘Tau, mementes, aurumina.’ His hands spin the elements around him. In the heart of the machine, power conduits open. Fire and coolant flood the larger systems. Borealis Thoon shivers. Chains rattle against its armour. On its back, the twin sets of tri-mounted turbo lasers pivot in their mounts. Sparks run over their barrels. The metal fist of its right hand flexes with a melody like the snapping of girders.

Hydragyrum feels the sensations of his machine waking, and keys the vox link to Tual.

‘We wake, Custodian,’ he says.

Beyond Borealis Thoon’s eye ports, the Lychway boils with light. Red clouds swirl out of the distance. Blue and pink lightning threads the air. The alien pillars are glowing with a cold blue. The stained cloud arcs above the Titan, crackling with darkness, breathing shadow.

Hydragyrum watches it, knowing that a human would have felt terror, or confusion. He feels nothing, though. He is an empty vessel shaped like a living creature, but that is as it should be. He was the lodestone at the centre of the tree of death, the absence at the heart of annihilation, the null to the aleph of life.

Daemons form in the red cloud, blurring with ragged shapes as they bound over the pillars and buzz through the air. Every shape of nightmare rolls in the murk: flayed hounds, spinning masses of limbs and light, rotting insects as large as battle tanks.

The Lychway shakes. Pillars shatter.

The governor called Silence whimpers from her place beneath his throne. Her mouth is sewn shut, her tongue taken. The whimper pulses through the Psi-Titan’s body instead, and Borealis Thoon roars into the oncoming storm.

‘Animus,’ says Hydragyrum, and turns the crucible into the first of its greater alignments.

Deep in Borealis Thoon’s body, the sleepers wake. They have lain in their crystal coffins, dreamless, their bodies wrapped in amnion. Each of them is a psyker, and as each of them wakes, they scream. Psychic power lashes through the Titan’s frame. Lightning and frost rolls across its skin. Unnatural energies rush though aetheric conduits and meet the blackness at the Titan’s heart. In his throne, Hydragyrum watches as the symbols of the four cardinal elements shift into alignment and begin to orbit him. Warp power is spinning around the darkness of his presence like a cyclone, accelerating and growing.

‘Aetherica,’ he says, and nudges the orbiting symbols into a different path.

The power rolling over Borealis Thoon vanishes. A wave of stillness ripples outwards. The tide of daemons falters. Creatures of blurred furry and stolen flesh slow in their stride. Cries hoot through the air.

At Hydragyrum’s feet, the last of the trio of governors convulses. This last human has no eyelids and his mouth is an open cave of metal. Interface cables slot into his skull on each side where his ears once were. He is called Pain, and as he screams without sound, Borealis Thoon begins to walk.

The wall of daemons bends backwards, churning like the sea retreating from the shore.

Blackness gathers in the maw of the weapon that hangs from the Titan’s left arm.

On his throne, Hydragyrum waits until the control sphere is a blur. Then he sits back. A single, obsidian globe spins to stillness just in front of his left hand.

The daemonic tide is rippling as the pressure pushing it forwards backs up behind its faltering charge.

‘Nul,’ says Hydragyrum, and taps the globe.

The sky above Terra was blue. Pollution hung in a haze that ran to the edge of sight. Prefect Hydragyrum walked alone along the top of the Sinopian Wall towards the Anatolia spires. Sunlight caught the subtle patterns of thorns woven into the black fabric of his coat. A high collar ringed his neck. His head was clean-shaven. Silver plugs capped the mind interface sockets at the base of his skull. Black tattoos covered the left of his face, turning half of his sharp features into a mask of nightmare. Anyone who could look at him for long enough to note any such details would find no insignia or sign of office besides the lion’s head ring on his left index finger.

And no one he passed looked at him. They turned their eyes and hurried away. If asked, none of them would be able to say why they did not want to look at the thin man in black. A lucky few would say that they could not remember him at all. That did not bother Hydragyrum.

Outwardly, he seemed a human just like those that passed on his walk across the walls. He was not human, though, any more than a statue of a man was a man. He was inhuman. He was pariah. He knew this, and had known it ever since he had been old enough to hold a thought. He presumed that his family had seen it in him, which was why they had left him on the refuse range to die – the strange child with the eyes that made people shiver, and who did not cry when they left him to the wolves and winds.

But, like everything in the pattern of the universe, he had his place. A place and a purpose.

He walked on along the top of the walls. Lifter towers marched across the flanks of the defences. Huge blocks of raw stone swung up into the sky in the jaws of cranes. When the wind shifted, he could hear the rhythmic calls of labour gangs as they hacked and hammered at stone and steel. The Palace was different from when he had last walked under the sun. While war raged in the tunnels beyond the Emperor’s dungeon, a different face of the same war had come to the world above. Neither the war beyond the Golden Throne nor the growing fortress above had touched him in the buried stronghold of Borealis Chamber, far to the north. He and his machine had waited long to be called.

He paused for a moment on the crest of a flight of steps, and spent exactly two minutes watching the flow of movement amongst the labourers. He would be on time even with this delay. The walk had helped him balance his body’s humours. That was good. He needed to be ready for the debate. The wind skimmed the bare flesh of his scalp, and flicked the edge of his coat as he turned away.

The sound of armour and active weaponry filled his ears as he began down the steps again. A giant in amber-yellow battleplate barred his path, weapon levelled.

‘Identify yourself and give reason for your presence.’

Hydragyrum tilted his head. The giant was one of the Imperial Fists, a veteran, 675th Company, twenty years since induction according to his honours and unit markings. The willpower that the warrior was showing by confronting Hydragyrum was impressive. To look at him for so long must have caused the Space Marine actual pain.

‘Allow me to pass,’ said Hydragyrum. He knew what must have happened. The ring on his finger had unlocked every portal and door he had come across since he had risen from his chamber’s Arctic stronghold and come south. The Imperial Fists had noticed his presence on the wall, and backtracked to find out that he had gained access via a cypher key. They would not have been able to identify the key’s origin, and so they had come to find out who walked so freely in their domain. The fact that the access codes held in Hydragyrum’s ring were valid and exotic was likely the only reason that this warrior of Dorn had not gunned him down on sight.

‘You will answer, or you will die where you stand,’ said the legionary.

Hydragyrum turned his gaze full on the warrior. The monster of armour and gene-crafted flesh visibly flinched, but held his aim steady. Hydragyrum turned his left palm over and tapped the ring with the tip of his thumb. A cone of holo-light sprang from the ring. The image of a lion’s head rotated in the projection, sunlight bleaching the image but somehow robbing it of none of its ferocity. Rings of data and information spun around it.

The Imperial Fist gazed at it for a second, and then stepped back, dropping his aim and bowing his head briefly.

‘My apologies,’ he said.

Hydragyrum lowered his hand, the authority of his ordo vanishing. He looked at the warrior for a second and then walked on without a word.

When he came to the Tower of the Sickle Moon, the assembled Custodian Guard did not try to bar his path. They knew better. He ascended the seven hundred and seventy-seven steps to the chamber at the tower’s summit. Three figures waited for him: a Custodian, one of the Silent Sisterhood and a tech-priest. Hydragyrum took each of them in as he crossed the chamber floor. His eyes noted the geometry of the architecture, the subtle and obvious symbolism of angles, the placement of flame for light, water for reflection, and black stone for the table at the centre of the room. Four silver cups sat on the tabletop. He walked to his place.

‘Your names?’ he said.

The Custodian flicked a glance at the null-maiden. She remained still, her eyes unblinking and icy above a silver mask.

‘I am Tual,’ said the Custodian.

‘That is not your full and true name,’ said Hydragyrum

‘The thread of my true name is mine alone. Be satisfied with Tual, prefect.’

Hydragyrum considered, gave a short nod and looked at the Silent Sister. She met his gaze. He wondered for a second if the other two presumed kinship in that look, the two soulless ones finding themselves mirrored in the other’s eyes. He felt nothing, though, and if the null-maiden did then she gave no sign.

‘I am familiar with your symbolic gesture system,’ he said to her. ‘You may use it to answer me.’

She raised an eyebrow and flicked her fingers.

‘Varna,’ he said aloud. ‘My thanks.’

‘Agates-Gamma,’ said the tech-priest, in turn.

‘Tual, Varna, Agates-Gamma. I am named Hydragyrum. I am the Fourth Prefect of the Borealis, and I answer your call.’

‘You are late,’ said the tech-priest, his voice a rattle of tiny gears.

Hydragyrum ignored the words.

‘What is it that you would ask of the Ordo Sinister?’ he asked.

‘We ask that you walk to war,’ Tual replied.

The beam rips across the space between Borealis Thoon and the tide of daemons.

Blackness runs down the beam’s core. Light shatters around it. Sound flattens. Screams, howls and hoots lose distance and volume. The beam strikes. The first daemons in its path vanish. One moment they are bounding forward, and the next, they do not exist.

The beam begins to shriek. Cold light whips around it. Colours pour into it.

The daemons run, clawing at each other, leaping up the curved walls of the Lychway to get away from the darkness shearing through them. They are creatures without fear, without the nature to feel any true emotion. Yet they run from Borealis Thoon.

Hydragyrum watches as the beam carves through them. The crucible is spinning into a new alignment around him. Borealis Thoon will not be able to maintain fire for more than a few more seconds. He pushes the black globe back into orbit amongst the elements spinning in the crucible.

The beam blinks out of existence. Light and sound roar back into full force. The daemons hold still for an instant and then flow down the walls again.

The third and first cardinal elements are smoking as they spin past Hydragyrum. Blood will be staining the amniotic caskets of the two psykers. They will last only a little longer, but Borealis Thoon has other teeth. The crucible slows its spin. Hydragyrum reaches for the sigils for sulphur, fire, silver. The turbo lasers on the Titan’s back gather charge.

The daemons cross the distance in a stuttering blink. Their substance thins as they close. Flesh unravels from them like sand blown from the face of a dune.

The turbo lasers fire. Sun-white beams lance out, punching into the horde, cutting through plague-bloated bodies, blasting gleaming skin and muscle to black slime. Inside Borealis Thoon’s skull, the governor named Silence is breathing hard, trembling with the connection to the machine’s weapons.

The daemons keep pouring down the spiral of the Lychway. The glowing tips of alien pillars project from the surface of the swelling flow of monsters. The air is blazing with ghostlight.

Slaved weapons fire from beneath the Borealis Thoon’s carapace. Bolt-rounds and las-fire sleet down as the flow of monsters spills around its feet. Fanged mouths bay in its shadow. Ash falls from them as they try to hold on to their forms.

Hydragyrum notes the daemons’ proximity as a flash of hololithic light in the crucible. Elements and symbols shift to his will. Void shields snap into being around the Titan, wrapping it in layers of energy. A pulse of telekinetic force rips out from the Titan’s body, and half-dissolved daemons scatter into the air. Borealis Thoon strides into the sea of horrors. The Lychway quakes under its tread. The ghostly substance of the webway trembles, as though fighting the presence of the Titan. Bone and crystal pillars shatter as it passes. Hydragyrum notes each effect and alteration, and pushes Borealis Thoon on into the tide even as it rises to meet him.

The plan had been simple, its need direct. The war waged in the labyrinth of the webway was not like battles fought on planets, or in the void. The enemy faced by the Custodians, Sisters of Silence and machine-cultists was endless. The daemons of the warp could not be killed. Their power would wax and wane. Sometimes they were few, sometimes they were numberless. Their strength could be terrifying and it could not be defeated. It was a constant pressure beyond the walls of the webway, always trying to find a way in, always seeking for weaknesses. The aim of the Emperor’s forces was not to destroy the daemons, but to push them back and shut them out of the sections of webway that they could hold.

It was not like fighting an army. It was like trying to control a wildfire.

Lightning crackles through the air before Borealis Thoon as it marches up the spiral curve. The daemons retreat before the black Titan, but they are not defeated. Hydragyrum has faced them before. He can read the pattern of their disorder. Just as the brightest flame brings the largest insects to its light, so does the greatest battle attract the greatest of daemons.

The horde of lesser creatures parts, draining from the broken pillars. Bloated things of forge-red metal and bleeding muscle scuttle forwards. Some hoist into the air on tattered wings. They grow as they move, sucking aetheric power into themselves. Multi-coloured fire pours at Borealis Thoon from every direction. Glowing bullets rattle into the air and kiss its void shields. The layers of energy shimmer, popping and foaming with explosions.

Hydragyrum feels the fields begin to flutter. His mind is a blur of transpositions as he tries to reshape the intricate balances of the Psi-Titan. A telekinetic enfolding could make them proof against the deluge, but only for a time. If he shifts the aetheric elements to repel the daemon engine’s fire, then they will be expended. Renewal will take time. That is why the void shields are there – to buy him precious minutes more.

The half-machine daemons are swarming forward, spitting energy and acid. The light beyond the Titan’s eye ports is a migraine smear of colour. The first layer of void shields collapses with a whip-crack of thunder. Then the next, and the next. The crucible whirls, elements moving out of alignment. Hydragyrum feels his muscles clench as he braces.

The first kiss of daemon fire touches Borealis Thoon’s metal skin.

The Titan shudders in pain and rage. Hydragyrum feels it. He is not a creature of emotion, his soul a black mirror that reflects no light of joy or anger. But he feels the rage and pain of the machine he walks with.

His hands snap the crucible around. The governor servitor called Pain vomits blood from the plug of his mouth. Worms of witch-fire wash through the Titan’s bridge. A glowing arc earths in the sphere of the crucible and vanishes. The obsidian globe spins towards Hydragyrum’s fingers and he catches it from the air.

The beam of unlight lashes from Borealis Thoon’s left arm. The half-machine daemons cease to be. Hydragyrum holds the crucible still as the elements try to wrench free of the alignment he has set them in. The Titan is shuddering as it walks. Light is falling into it, spiralling into its shadow. The three governors beneath Hydragyrum’s throne spasm. The black beam of annihilation continues to pour from the Titan, slicing through daemons like a scythe set to corn.

Then the beam is no longer there.

There is a stitch of time, a second pulled out to an eternity.

Hydragyrum still has his hand on the black sphere, but two of the four cardinal elements have swung out of place. Data spirals around him. All of it is red.

‘Alkahest,’ he says, and yanks two levers set into the right arm of his throne.

Deep within Borealis Thoon, two blood- and amnion-filled sarcophagi pull out of their sockets as machine arms hoist them away. Cables and pipes snap free of the crystal cases. Cooked meat and blistered skin floats in the sloshing fluid. For a brief moment, both sarcophagi hang, and then they drop through a hatch and into the waiting fire. Fresh caskets are already in place. Cables lock into their sockets.

‘Animus,’ says Hydragyrum, high up in the Titan’s skull.

The figures in the crystal sarcophagi twitch. Drugs pour into their veins, ripping back the comfort of sleep. Frost flashes over the cases and up their conduits. Matrices of crystal threaded through the Titan’s bones light with fresh fire.

Hydragyrum watches as the four cardinal elements begin to turn again. The psykers will be wakened and ready within seconds, but he does not have seconds. Out beyond the Titan’s eyes, the daemon tide is deepening as bodies scramble and pile over one another, like wasps crowding a queen.

Something is bulging beneath the carpet of horrors.

‘Aetherica,’ he intones, and power lashes through the Titan. He flushes it to the turbo lasers and void shields.

The rearing carpet of daemons peels back. The creature beneath is a sculpture cut in darkness, outlined in furnace glow. Its form swells, billowing up to fill the curve of the tunnel. Jaws yawn wide, fire framing the night-filled mouth within. Its shape changes as it grows: shadows of wings, hints of muscle and quills, glimpses of blisters and burning eyes trapped in a serrated shadow.

Hydragyrum cannot see this daemon. His mind offers it no mirror of fear.

Darkness – the blind governor of the Titan’s sensors – can see the creature, though. Its image uncoils in the crucible’s holo-projections. The monstrous shape flickers, looming, a vast blister of abomination forced through the skin of sanity.

The elements of the control crucible spin faster. Borealis Thoon’s psychic might is ascending, but it cannot be brought into alignment yet. Hydragyrum smiles. The daemon before him has waited until just this moment to manifest. While the fresh psykers mesh with the spirit of Borealis Thoon, it is just a Titan like any other.

‘Clever,’ he says to himself, and fires the turbo lasers.

Spears of sun-bright fire stab at the daemon. It changes, flowing forwards like a flock of carrion birds. Borealis Thoon turns, weapons pivoted, slicing fire after the creature.

It is faster.

It passes through the Titan’s void shields with a rippling boom. Curtains of light flash into being and vanish. Hydragyrum steps the machine back, but the daemon is rising, its scattered form gathering into a serpentine body. Its substance is blurring, dust and shadow spilling behind it as pushes against the presence of the Psi-Titan. Lesser creatures would be destroyed by the close presence of Borealis Thoon – but this beast is an exalted thing of Chaos, and the warp pours into its being faster than it can be unmade.

A long head of scales and teeth forms at the end of its body as it coils around the Titan. Hydragyrum can see only darkness beyond the Titan’s eyes. In the holo-projection, the daemon’s mouth opens again with a scream of burning cities.

‘What you are proposing is–’

‘It is the will of the Omnissiah,’ snapped Agates-Gamma. The tech-priest’s eyes whirred, and the green lenses snapped to red.

Hydragyrum turned his gaze on the man. ‘The Emperor wills and Borealis obeys. The ordo obeys. All obey,’ he said, voice flat and level. ‘But you are not His voice, nor is your will His.’

Agates-Gamma bridled. Chrome and brass mechadendrites coiled over his shoulders.

‘Prefect Hydragyrum–’ Tual began, the Custodian’s voice a smooth rumble.

Hydragyrum decided instead to clarify his point.

‘The Emperor’s will is that the war in the tunnels beyond the dungeon be won,’ he said. ‘You are correct in that. Our ordo and the Chamber Borealis has served in that endeavour. We knew then that He willed that we walk the labyrinth. But that does not mean that He wills us to take this place in it now. The past is not the future. If He wished it otherwise, He would command us.’

Tual held Hydragyrum’s gaze. The Custodian did not flinch. They rarely did, even when Hydragyrum focused his entire attention on them.

‘If your chamber will not agree,’ said Tual, ‘then the proposition can be made to one of the others.’

Hydragyrum shrugged.

‘You may approach them,’ he said.

You believe that they would refuse? Varna asked the question with quick movements of her fingers. Hydragyrum turned his palms face up on the tabletop.

‘They may or they may not,’ he said. ‘Your plan is to relieve pressure on the main transits of the webway that we still hold. You intend your unifier artisans to shore up and extend the sections behind. You also hope to annihilate as much of the daemonic incursion as you can, so sapping their strength for a time.’

‘You believe that the scheme is flawed?’ hissed Agates-Gamma.

‘You are proposing provoking a large-scale incursion of the neverborn into the webway, and then channelling it into a single location where its energy and substance can be nullified. At best, it is a temporary relieving of the pressure that they are exerting on our forces in the tunnels. Like bleeding a fever victim, or letting fire consume the forest it feeds on. It is not a cure.’

Tual turned his head and reached for the helm clamped to his armour. The gesture had the finality of a falling blade.

‘Very well,’ said the Custodian. ‘You have our thanks for attending, prefect. We will explore other options.’

‘I did not say that we would not comply with your request,’ said Hydragyrum.

Tual looked at him, a frown creasing the Custodian’s face. Agates-Gamma stirred and shifted, his servos and gears clicking in puzzlement.

‘Your previous statements held a contradictory implication to what you have just stated.’

‘I stated facts. I did not offer a denial,’ said Hydragyrum, tilting his head to look at the tech-priest. ‘I would hope that one of your caste could appreciate that.’

So you will walk with us? Varna signed.

‘No,’ he said. ‘We will not walk with you. I will walk alone. When the tide comes I will face it, while you do what you need to.’

‘But–’ began the tech-priest.

‘All of your forces will have their parts to play – the beasts must be driven to the killing ground. But I shall be the reaper.’

Why? asked Varna.

‘Why have I agreed, or why do I say that I walk alone?’

Both.

‘I agreed because no other can do what you need, because you were not created for annihilation no matter what use our master puts you to, because the Ordo Sinister exists to face such foes. And I agreed because He would wish it even if He has not ordered it.’

Silence followed his words. The null-maiden, Custodian and tech-priest were watching him with unblinking intensity. One after another, they nodded acknowledgement.

‘The Ordo Sinister shall walk,’ he added.

Fire cloaks Borealis Thoon. Black lacquer blisters on its skin. The daemon serpent vomits flame as it spirals around the Titan. The tide of lesser daemons surges forward like plains-jackals and carrion feeders made bold by the bleeding lion.

Inside the Titan’s skull, Hydragyrum feels scorching heat spread over his skin. He is a psychic void, but he is linked to the Borealis Thoon by neural interface, and its damage is his pain. The air is vibrating as the crucible rotates in a blur.

He needs time. He slams two of the cardinal elements of the crucible into sympathy with the thirty-fourth hexagrammatic resonance, and the fire in Borealis Thoon’s bones cools. Its heat-blistered skin shimmers, damage vanishing as though it had never been. The daemon serpent hisses, and the fire pours from its throat, so hot that its core is blue, its edges white. Ice forms where the flames wash the Titan’s skin.

The Lychway is quaking. Alien pillars shatter and fall, splinters shattering and burning in the psychic gale. Lesser daemons circle in the air and on the tunnel walls, eyes bright with fear and thirst. Bolt-shells and las-blasts rain down from Borealis Thoon, cutting a circle through the waves of creatures boiling around it.

The daemon serpent rears in Hydragyrum’s holo-display. His hand plucks the rune of iron from the air as the crucible spins it past him. Iron is the basest element in all those that he can wield, its control represented by a lump of raw ore. Rough lines cross the lump’s surface, forming words that have been dead to mankind for over thirty millennia.

Hydragyrum grips the iron and punches. The serpent is directly in front of Borealis Thoon, hooded in fire, flowing like a silk ribbon snapping in the wind. The Titan’s power fist lashes forward. Ghost-ice scatters from fingers the size of tank barrels as they snap shut around the serpent’s throat. Lightning sheets out. Cold fire arcs from the closed fist. The serpent writhes, spewing flame, its shape flickering and sliding between muscle, feathers, flesh and smoke. The Titan squeezes, pouring its essence into its grasp, strangling the creature, eating its essence.

Hydragyrum is sweating. Feedback is bleeding into him across the neural link in his skull. The crucible’s current alignment cannot hold for much longer. The elements are pulling apart. The universe abhors stability, and the controls of a Psi-Titan are the universe distilled and transmuted into symbols, levers and movement. He holds on, siphoning the power of the Titan into its fist. He needs to hold it just a little longer.

The daemon becomes still in the Titan’s grasp.

And then it is not a creature, but an expanding column of fire and black smoke. It reaches up, spreading across the Lychway in an anvil-headed cloud. The blast wave tears lesser daemons apart and spins them up into the embrace of a cyclone. Borealis Thoon staggers. Its right arm is a stump of shredded metal. Hydraulic fluids gush from it. Its front is burning. Ghost-light writhes across its wounds. The metal of its skin flows, trying to knit back together as it straightens.

Hydragyrum is bleeding. The shockwave has burst his eardrums and the soft tissue in his nose. Blood is staining the whites of his eyes. The taste of wet iron fills his mouth.

‘Custodian… Tual…’ he hisses into the vox.

‘Prefect,’ comes the reply, growling with static.

‘Is the incursion into the Lychway at its peak?’

Static fills his ears. The daemon is congealing from the fire and smoke before Borealis Thoon once more. Hydragyrum wonders who will bear his name and the name of his machine. For a moment – for the first moment in a life where he has never understood what it is that mundane humans feel when they say they are moved by the moment – he finds that he would have preferred not to have needed to be here at this moment, and at this place.

‘The neverborn’s force is at its greatest, prefect,’ says Tual, the words flat and echoing over the vox. ‘You may withdraw.’

But here he is.

Four cardinal elements slide into alignment around him. The obsidian globe spins to within reach of his hand one last time. At his feet, Darkness spasms, smoke fuming from her skull, and then lies still. The image of the daemon vanishes from the hololithic display.

‘Nul,’ says Hydragyrum, and Borealis Thoon roars pure blackness as the fire falls.

The sky was fading from blue to purple and black when Hydragyrum stepped from the base of the Tower of the Sickle Moon and back onto the Palace walls. He paused. The lights of starships and smaller aircraft winked across the darkening heavens. Halos ringed the brightest of the false stars as their light fell through the haze of pollution. The true stars were still emerging, their brilliance stolen by the glow rising from the Palace. His eyes moved between the ancient patterns of constellations, noting the relative positions of each.

‘What do you see in the stars?’ came the voice of Tual from behind him.

Hydragyrum did not turn. The Custodian’s armour buzzed with an electric melody as he came to stand next to the parapet. He had his helm in place. Its red plume stirred in the wind rising from beneath the wall.

‘I see…’ began Hydragyrum. ‘I see that the winds of destruction are rising. I see that the Hunter is bright in the heavens. I see that things change, and things end.’

The Custodian shifted, the red crystal of his eye-lenses turned to the darkening sky.

‘You know that the arts of astromancy and astromathics are forgotten by most, and would be considered a denial of the precepts of the Imperium by many.’

Hydragyrum shrugged.

‘Everything has its place in a greater design, a place where it belongs for a time. Just as clawed Karkinos must rise and, as it does, the Candle Bearer must fall. They are not free, or slaves, or good or evil. They just are. That does not change whether it is forgotten or agreed with.’

‘You make superstition into wisdom.’

‘I had a fine teacher,’ said Hydragyrum, and paused, his tattooed face very still as his eyes moved across the constellations above. ‘He once told me that He remembered when the stars had different names, and humans thought themselves alone in a universe that rotated around them, and them alone. Of all the lies of the past, Custodian, I think I like it best.’

He stepped away from the parapet and began to walk along the wall towards the dark vault of the sky. Tual watched him for a second – a lone man in black, stepping across the worn stones, the night swallowing his shadow – and then the Custodian turned and went his own way.