In my years serving the late Lady Theodora, I never stepped foot inside the Kiava Gamma main manufactorum itself, cogboys being jealous of their secrets, but I had guessed a few things. My imagination, however, came out short-changed when confronted with the reality of of it. When our distant forbears, on faraway Terra, first tempered the first steel — first powered the first engine, first built a manufactorum and stood in awe at our species' ingenuity — did they guess, in their dreams, the terrifying might their descendants would wield? We advanced along a gangway or balcony of sorts, over a chasm filled with molten metal; its reddish gleam reflected on titanic gears that turned chains and mechanisms the likes of which I had never seen. On our left side, at intervals, opened lightless corridors that gave a mephitic breeze. We stopped once by an open control room full of malfunctioning servitors and cogitator screens that spouted a headache-inducing nonsense. The Magos exorcised evil from their code and powered them all down.

Our advance was slow, made slower still by the lack of auspex. We were reduced to counting the number of passageways to plot our position on the map. And I have written nothing yet as to the noise! A perpetual hum resonated in our bones; the clang of distant hammers, the whine of nearby machines, the roars and hisses of unknown parts, all conspired to drown every attempt at conversation that wasn't relayed by our comm-beads. Magos Pasqal had, using our maps as well as some orbital data of energy usage, taken an educated guess as to where the heretics' control centre could be, and we followed his lead. In the fashion of his kind, he often absent-mindedly streamed out binharic arias of alarm; their broken rhythm was sung directly into our ears and spoke of unseen danger. It was nerve-wracking, really. A less seasoned party might have broken here and then. We, however, pushed through, wondering at the lack of opposition, and even more at the absence of bodies. We did break once through a cogitator, finding worrying logs speaking of new protocols implemented under the Fabricator-Censor's impetus — of Standard Procedures being shelved, even, and the Quest for Knowledge being replaced by a search for Truth. Master van Calox looked grim.

The first inkling that we were on the right track was finding a tech-priest in bedraggled robes at an intersection. The man was clearly sick in the mind: it took him three attempts to ask for our identification.

'Request denied,' replied Magos Pasqal. 'Registering anomalous behaviour within this servant's organics and an invalid noosphere response. This unit is compromised,' he told us.

Indeed, a black border of necrosis spread out from around the cogboy's implants, his body rejecting what they call the True Flesh. He moved, and a stench of rotten meat flowed to our nostrils. Wary, Her Ladyship nonetheless told him she was the mistress of this world, and asked him who he was. His external cogitators whirred for so long I wondered if we shouldn't rather abandon him to his fate and carry on our search, before a cracked voice came from his malfunctioning vox.

'Irregularity. Execution of the Fabricator-Censor-approved Protocol 39-42 recommended.'

'What is this protocol?'

'A sacred decree passed by the Fabricator-Censor that dictates the course of action that tech-comrades of Kiava Gamma in suboptimal working condition are to follow. Immediate execution of Protocol 39-42 recommended.'

So the tech-priest wasn't so far gone as not to recognise his own impairment! Before I could decide if that was a good thing or not, Magos Pasqal interjected that, the catechism of protocols having been distorted, he recommended adherence to the standard procedures of reconnaissance and purification. A short altercation in binharic followed. Her Ladyship understood it no more than I did, and just as she said that she wouldn't follow any protocol imposed by the Fabricator-Censor anyway, a bunch of skitarii, combat servitors, and heretek magos, come out of nowhere, fell upon us like fleas on an unsuspecting dog. I shall therefore take a wild guess and suppose that Protocol 39-42 was short-hand for 'call in reinforcements when faced with intruders.'

By the time we were done purging the world of the assailants' filth, — grenades and bolter rounds having put the metallic walkways to the test — I was feeling confident we could take anything Kiava Gamma would throw at us. Someone has given dear Lady Cassia a shotgun, and she takes even more pleasure firing it than she does lobbing grenades. Magos Pasqal began leading again the way, but Her Ladyship shook her head and pointed to the other side — to the hanging bridge that had lead our assailants to us.

'I'd rather find where this lot came from,' she said, pushing a stained red robe with her foot.

'Lord-captain,' I interjected, 'this might be unwise. The map says there should be some sort of overhang with many exhaust ports on the other side of the bridge. While it might be safe for tech-priests who are more metal than flesh, I cannot advise, in good faith…'

The lord-captain interrupted while reloading her longlas power-cell. 'Abelard, if the enemy still has reserves over there, I'd like to know it before they flank us.'

Rightly enough, once we had crossed the bridge and gotten on a vertiginous platform elevator, we were met with many warning signs threatening trespassers with the Omnissiah's wrath if we stepped into the area beyond the landing. The landing itself, though, was spacious enough, and we found evidence of it having been used as a makeshift guard post. Empty now, of course, which I found most satisfying. It was quieter up there; we could just about hold a normal conversation.

There was no seeing much beyond as vapour jets, hissing at intervals, shrouded everything in mist.

Well, of course the lord-captain wanted to check that area beyond the jets was secure too, so we had to play hide and seek with those scalding exhausts, seeking shelter between chimneys and giant vats when pressurised steam erupted. We mostly avoided the worst of the burns.

To my surprise, there was another clear area beyond the exhausts — one unmarked on our map. We probably would have been happy with a cursory inspection and left, if not for a few trip wires Sister Argenta spotted in the gloom. They had been clumsily installed and were easily defused, but if someone takes the trouble to set up traps then there is something interesting beyond, so we persisted. Sure enough, for our pains, we found a hiding place behind empty crates; not even a shack, as that would require a roof. There stood a cogitator with two screens, and there cowed a tech-priest: a scrappy creature in torn robes, with the underwhelming look of simple lexmechanics, who fell to his knees and begged for mercy.

How filthy he was! His robes were soiled with things I didn't care to know the name of. His many augments, however, looked healthy — except for a detached cerebral cogitator that hanged loose against his head, broken data-tethers dangling from his ear in a most miserable manner. Her Ladyship, with her ever renewed will to give people the benefit of the doubt, told the lexmechanic he had nothing to fear from us, as if Sister Argenta hadn't trained her bolter on him. For good measure, Magos Pasqal reassured him in a binharic flourish of notes.

'Deus Mechanicus,' cried out the shaking tech-priest. 'My prayers have been heard! I thought I was alone in a kingdom of madness and depravity! Please, save me!'

Our Sister of Battle wasn't the only one still wary, though, as Master van Calox, all cloaked in inquisitorial sternness, ordered the man to tell us his name and story.

'Manufactorum lexmechanic Zeta-86. I performed the rituals for the machine spirits of Foundry 95… up until we started going mad.' The priest kept a humble stance, as if understanding of our need to ascertain his mental health. How small and miserable he looked compared to our own Magos! The difference in standing was as between a conscript and the Rogue Trader herself. While I mused on the way appearances can be trusted in such matters, Lexmechanic Zeta-86 explained that priests previously fully devoted to the Omnissiah had, all of a sudden, started praising what he called 'the dawn of something or other.' Belts had been stopped. The visages of the sacred machines had been desecrated with unholy symbols.

'Some of them resisted,' he continued. 'The others grabbed them, tied them up, and then… and then…' His voice fell to a whisper when he avowed the tech-priests' implants had been forcibly turned to heresy. 'I saw the madmen, my former tech-comrades, deliberately connect those poor souls to corrupted cogitators… I watched as they were infected with the scrap-code…'

If the lexmechanic had felt bad about this (as he should have), Magos Pasqal turned the knife in the wound when, in an icy rumble, he said: 'And you did nothing to stop them. I am recording a violation of the commandment Of thine forge be a true sentinel. Apostate Zeta-86, your accesses are hereby revoked. Proceed with your report.'

Glaring daggers at the Magos, Her Ladyship kindly asked the lexmechanic how he had avoided the same fate. He cowered with shame. It was several instants before he could speak again, and when he did it was with the rush of a death-bed confession.

'I… I didn't avoid it. They performed the same procedure on me. I felt the touch of unholy code. I allowed it to control me. I abandoned my sacred post and followed one of the traitors, serving his will and gathering all the data for his blasphemous experiments. I was driven by an unholy impulse coming from the depths of my auxiliary cogitator, where the code had lodged itself.' The man, overwhelmed with guilt, made the sign of the Cog. 'Before I found a way to throw off the compulsion, by tearing out my auxiliary cogitator from my skull in purifying pain, I witnessed horrifying heresy… the extraction of True Flesh and its decomposition on altars… perverse procedures that resulted in heretechnical abominations. I even accompanied a fallen Magos to the Fabricator-Censor himself and attended the unholy mass he led personally, with one of those renegade Astartes monsters! It was a wicked ritual, full of wilful deviations and blatant inaccuracies, all to create an ungodly contraption in the name of their final dawn!'

Master van Calox drew a deep breath of satisfaction, as one who finds the trail he has followed across the stars is still hot.

'Where is the rest of the population?' asked Her Ladyship. 'Those who aren't tech-priests.'

'The lay servants of the main units? They live in isolated segments under the sacred machine halls. I… I heard the survivors have been imprisoned somewhere, that my crazed brethren may conduct some depraved experiments on them… building a nightmarish parody of a sacred machine, powered not by the Omnissiah's grace, but by the unholy spirit and life force of the unfortunate!'

Taking a few steps that barely resonated over the metal floor, our Interrogator considered the tech-priest and loudly observed the man demonstrated exceptional powers of observation and recall for someone who, as he put it, just happened to survive. I was reminded of a predator circling its prey. The tech-priest protested that he was a lexmechanic, that gathering data was the purpose of his existence — that it had been the very way in which the heretics had used him against his will. The dangerous glint in van Calox's eye was unmistakable: the predator was about to take his prey at the throat. Tilting his head, he said: 'Servant of the Omnissiah, I must know more. About the Final Dawn, the Fabricator-Censor, his mass… and about this machine as well.'

Like most prey, the small lexmechanic was oblivious to the danger that hovered around. He raised his head, gazing up at van Calox's towering silhouette, and said that yes, he could give him the coordinates. But there was a catch that made his voice droop in anguish.

'As for the machine, and the mass… Even though I was present for many blasphemies committed by those heretics,' he regretted, 'all the details that were captured and processed by my True Flesh are in the augmetic that was corrupted by the scrap-code instead of my biological components. I am convinced that if I hadn't fought off that foreign compulsion in time, I would have been doomed — the corruption would have spread to my biological cogitator as well.' He tapped a finger on the device hanging loose at the side of his head and cursed it in binharic. 'I swore that no devout tech-priest should come into contact with what's hidden in that once-sacred device! Even if the very idea of exposing a holy machine to the scrap-code wasn't profane in itself, my augmetics are not universally compatible — they cannot be connected to another machine spirit. They were created to interact within the system of my True Flesh, to innervate my compulsor unit and output data via the inscriber. Once I am safe, I swear that I will immediately perform a cleansing rite and destroy —'

'In other words, there is only one way to extract the data stored in the cogitator.' Van Calox's voice was quiet, his tone careful and deliberate. Only by connecting the corrupted cogitator back into the lexmechanic's biological brain could its content be safely extracted — condemning him to submit to heresy again, to lose his immortal soul to the Ruinous Powers! I looked with horror as the lexmechanic's eyes widened in fear, and I wondered if he would willingly forego such martyrdom for the sake of the Inquisition — sacrifice more than his life in the fight against evil. Before he could voice a reply, though, Her Ladyship stepped in between Lexmechanic Zeta-86 and van Calox. She held her hands behind her back and looked at him with a steady gaze.

'Heinrix,' she said. 'No. Don't do it.'

His voice turned dry. 'The lexmechanic could have been privy to conversations that are vital to investigating the cult. We need the contents of that cogitator.'

The tech-priest had turned deathly pale and begged not to be submitted again to the corruption of the scrap-code. 'Please,' he cried, twisting his hands in anguish. 'I'd rather be burned as a heretic than have the scrap-code spread to my biological cogitator!'

Ah, I couldn't blame the man. I've seen first hand what that scrap-code does to people; it cost us a few good bridge officers, and at least two excellent ones. It's a wretched way to go indeed. At the man's words, van Calox paused for a fraction of a second, as if he were reconsidering. This was the time, of course, that Magos Pasqal chose to impart us with his opinion on the matter. How he had refrained from doing so earlier I cannot guess, but what I know is that Her Ladyship will probably give him a dressing-down that will shake his mecha-dendrites all the way to Mars and back, judging from the look on her face when she heard what he had to say.

'In failing to offer any resistance against the enemies of the Omnissiah, Unit Zeta-86 lost the grace of his machine rank and was recategorised as a resource of the manufactorum,' explained ponderously our Magos. 'The defilement and torment of said resource, if committed to advance the struggle against heresy, will not be deemed an apostasy or malefaction against a living soul. Upon expiry of the unit's utility, disposal is recommended.'

I was most surprised, however, when it was Lady Cassia's silver voice that next interjected. She stared, quite scandalised, at Magos Pasqal and piped: 'Eques Terentius, Magos, wrote in the twenty-third tome of his works that sin is what happens when you treat people like things. The Rogue Trader herself introduced me to his philosophy; I cannot believe such a learned person as you would…'

Even tech-priests of the highest rank, it seems, are not immune to the universal frustrating experience of being contradicted by a teenager — perhaps even more so, since they lack the expertise conferred by family life — and Magos Pasqal took the binharic equivalent of a deep breath before trilling angrily: 'The tenets of the Omniss…'

The violent crack of a discharged laspistol shook the air. The lord-captain had shot at the floor (probably out of fear of hitting a pipe with fyceline or terrenic acid if she aimed upwards), leaving a rapidly cooling, red-hot crater the size of an apple in the thick metal at her feet.

'Shut up,' she said. 'Pasqal, if I wanted your opinion, I would have asked for it. Cassia, I thank you, but the matter is on Heinrix's own conscience.'

In the silence that followed, the rhythmic sighs of the steam exhausts somewhere behind provided a reassuring distraction. After glaring at all of us in turns — Sister Argenta and I tried our best to appeared unconcerned by the situation at hand as we had done nothing wrong — Her Ladyship turned again to van Calox.

'Heinrix, I cannot constrain you, nor your decisions. But the leaders of the cult would never discuss anything of importance in front of witnesses. So stop. Leave the poor man alone.'

'We need to know where the unholy machine is. Even if the heretics' conversations are unimportant, I must know why this device was so valuable to them!'

'I'll tell you,' exclaimed the lexmechanic, searching wildly through his clothes. 'I'll tell you! A different augmetic is responsible for my muscle memory. It has a data storage too, I remember where I walked and what I pressed with my fingers… here, here are the coordinates… and the code. It's probably the code to the bay.' Producing a scrap of parchment and a quill from his ragged robes, the wretch scratched a map and a string of numbers before passing the document to van Calox, who took it and read it unhurriedly. Master van Calox pursed his lips; he folded the parchment and put it in an inside pocket. No one yet dared to move: his unflinching eyes bore into the lexmechanic's. At last, having reached some conclusion, he turned to the lord-captain.

'He is a subject of your world, Katov. It is for you to decide his fate.'

Her own expression, that would have curled milk, softened a little when she looked down at the lexmechanic who, having understood she was the Rogue Trader and therefore his absolute sovereign besides his occasional saviour, prostrated at her feet.

'You will be taken to my ship. After the cleansing rites, a place will be found for you there; we always have need of competent lexmechanics. Go to shuttle bay Theta-Nineteen-Delta and wait for us.'

Never have I seen a man scurry away so fast! Her Ladyship had barely begun calling our pilot and enginseers to warn them of our new recruit that his bent, broken silhouette had faded between the mess of pillars and industrial silos and into the steaming fog behind. Master van Calox walked to the lord-captain's side; with an unmovable expression, he said: 'Excessive kindness, Katov, gets good people into trouble. Let's hope that the corruption only affected the disconnected augmetic and not his soul.'

Her Ladyship shot him a curious glance and, disconcertingly, took his arm as if she were going for a walk in the gardens of Janus.

'Ah, come on, let's go,' she said, 'we have bucket of heretical bolts to find.'

Now that we had coordinates, we (or at least I) felt more purposeful — but our general direction hadn't changed. We were still going towards the place where most of the energy was leeched off the grid, as per Magos Pasqal's guesses, and I suppose it made sense for a powerful heretical machine to be there. Our surroundings, however, soon became quite different: walls recessed; occasional control stations appeared, complete with cogitators and the remnants of blessed paraphernalia, which had been defiled. The heat became more oppressive.

Suddenly, we found ourselves in a place high as a cathedral — a rotunda built over assembly lines and open forges. The Machine God's holy sigils had been torn away, replaced by heretical displays, and in the middle of everything, on a hanging platform loaded with command panels, stood Fabricator-Censor Cubis Delphim and a few minions in red robes. Braziers, alight with purple flames born of the Empyrean, brought a terrifying glow to the Fabricator-Censor's arachnid shape, which had gotten worse since I had last met him. He was now a grotesque, hunched thing covered in tentacular mechadendrites; his vestments couldn't disguise the monstrous assembly of unholy metal he had become in mockery to the human race. From beneath the deep hood of his mantle, two dimly lit ocular implants watched us with open malevolence, and a binharic tirade of scorn reached us. Skitarii waited for us, too; our deceased adversaries must have taken the time to warn them of our approach. They merely kept us in their sights, though. The Fabricator-Censor, it seemed, wanted to have a chat with us from the safety of his platform. Her Ladyship eyed him with amazement when he launched in another binharic rant, and asked who in the void he was. Now that was insulting, of course, and the Fabricator-Censor's mechadendrites bristled with wounded pride. Still, he must have realised we hadn't gotten a damn clue of what he had been saying (except for Magos Pasqal, who was choking with indignation) and replied in passable Gothic that he was the steward of Kiava Gamma, before ordering us to kneel.

Her Ladyship, of course, did not kneel. She shrugged, took a few steps forward, casually lent on the railing and replied that she herself was the Rogue Trader of the von Valancius dynasty, and that she gave him five minutes to offer his final confession. From her vantage point, she had a better look at our foes' disposition and discreetly gave a few hand signs regarding their numbers and the way she wished we took our positions. The Fabricator-Censor, of course, was incensed and began deriding her in the arrogant manner of heretics, accusing her of having oppressed the tech-priests of Kiava Gamma and other nonsense. That was a confession, truly: he avowed to murdering poor old governor Gaprak to further his goals; he avowed to having renounced the Cultus Mechanicus and therefore the Emperor in his Omnissiah's aspect; he avowed having pledged his allegiance to what he called the 'true gods' in a flabbergasting display of heresy. Magos Pasqal lost no time in declaring the former Fabricator-Censor an apostate and traitor, and condemned his doings as anathema. Magos Pasqal gave a fine speech, sure of himself and his right, and when he ordered the cycle of blasphemous operations, as he put it, to be discontinued, I nearly applauded. What the former Fabricator-Censor took from this, though, was merely Magos Pasqal's name of Haneumann. Leave it to cogboys to focus on the least relevant part of discourse, if it's one that piques their interest! A Magos Dementz Haneumann, he pretended, served him — served him so much that he was the author of the scrap-code that had nearly cost us so much! I resolved here and there to slay that heretic!

Our own Magos's indignation was an excellent focus to distract our enemies' attention; Lady Cassia had been able to quietly find her way to a mezzanine behind us without raising alarm. Sister Argenta was creeping behind storage tanks to a place where she could entrench herself and rain the Emperor's wrath, in the shape of bolt-rounds, over the heretic skitarii. Van Calox and I stood ready to run wherever the frontline would be and he, at least, listened intently as Her Ladyship feigned ignorance to coax the former Fabricator-Censor into telling us more about the cult. It was such a jumble of words, how can Inquisitors make head or tail of this sort of ramblings? No wonder they are so quick to condemn. The former Fabricator-Censor spoke of piercing the veil of empty dogma to heed the call of the truth — of retooling Kiava Gamma to the cult's needs, that involved delving into mysteries once forbidden, so probably the worst heresy possible.

I couldn't wait to avenge governor Gaprak's memory; the dear man had once told me he had always been uneasy in the presence the tin-can comrades, as he called the esteemed Adeptus Mechanicus, and half complained of not having been dealt a normal planet. I shall have to honour his memory with a prayer, now we have finished purging this place. But back to my tale.

The Fabricator-Censor finally started repeating himself; Her Ladyship glanced down at her chronometer and told him his five minutes were done. Sister Argenta immediately opened fire; Lady Cassia pointed me to the nearest skitarii, that I was extremely happy to send flying back a few meters with a good whack of my power-hammer. She manipulated the Veil, hurting the heretics with the very Immaterium they believed to hold their salvation. Her Ladyship's longlas cracked like a whip and, while we got busy destroying the Fabricator-Censor's minions, he himself scurried away to safety like the coward he was. Really, cultists are barmy. Anyone with half a mind would have jumped us when we first came in, instead of lecturing us on the good their soul-killing heresy could bring if only we could look past the murders and destruction. Now, we had the advantage — and we fully seized it.

The battle was brief, but intense. Skitarii are a well-trained bunch as a rule, and even heresy couldn't change that fact. We suffered, thankfully, very little casualties. Once we were done, Lady Cassia was grazed on the leg (nothing a medi-kit couldn't fully patch) and my ears were ringing from an unexpected blow. Now, according to the lexmechanic's directions, we just needed to cross the cupola in order to reach our goal, and indeed there was an ornamented door on the other side that looked sturdy enough to hold a fair deal of secrets. On our way to it, we found the first signs of the devastation the cult of the Final Dawn had wreaked: a giant fan, that once merely moved the too-hot air below the cupola, had been repurposed into a meat grinder. Dismembered bodies — augmetics and implants savagely torn — were piled above it, waiting to be flung into its reddened blades. Their massacred remains would then fall far down in the depths of the manufactorum. The stench of the dead was hardly bearable.

And yet, it was nothing compared to what we found inside the locked section that hid Master van Calox's prize. Past that heavy door was nothing but abject torture. In a dark room — cavernous, badly lit by cogitator screens running lines of meaningless corrupted code, and cold, so cold! Warp-cold — we found what, at first, I believed to be piles of cadavers thrown in great cages. Oh, that they had been dead! Getting closer, however, we saw in Her Ladyship's luminator's beam they moved still. Broken limbs, glistening with a foul-smelling ichor, appeared to creep like slugs. Faces, open in two like too-ripe a fruit, oozed with pus, and they blinked. And I saw all of this flesh had been fused by sorcery: each mountain of naked bodies was a single mass of corrupted, twisted, tissues pulsating with depravity. Tumours flourished on them, carcinomas that bled a pale fluid. And from their many throats came mournful cries. Sister Argenta retched.

The Veil was so thin! I could feel oily tendrils of evil intent all around us. Shadows of sin clung to our steps. We waded in pools of wickedness. Numerous wires and pipes ran to the filthy cages. Bright blue sparks flashed intermittently in the darkness while the conglomerations of flesh twitched and shuddered. The cages were not here to prevent escape, of which the sorrowful, twisted things inside would have been well incapable; they were devices of heretical build, created to torment further the sentient mutated remains of those who once had been people — loyal servants of the Imperium. Unfazed by such horror, van Calox approached the closest cage, sword drawn, and looked.

'Careful, Heinrix,' said the lord-captain.

'It cannot bite. Look at it.'

Closer inspection only furthered my disgust. Appendages and limbs had been sawed off, leaving wounds seeping pus and slime — wounds that were agglutinating and sprouting tendons. Rods, impaled in a seemingly haphazard way through thoraxes and skulls, connected the monstrous thing to data-tethers. One the human heads that still had eyes — one eye half-blind with cataract, the other injected with blood — stared at us. From its throat came a rattle, a moan: Mercy…

Even attempting to speak appeared to cause it pain, but it bore it with resolve and forced out the words: Mercy… make it stop… Her Ladyship, revulsed, took out her laspistol, and shot the face. Flesh exploded in a fountain of lumps, stinking fluids, and bone shards. The gaping wound, however, closed on its own in an instant; a different face emerged from the fleshy depths of the pulsing thing, and a many-voiced whine of pain and fear rose from all the cages.

'What is this,' whispered the lord-captain. 'What is happening here?'

It is fair to say this horrible display put us all on edge; dear Lady Cassia grasped my arm, her poor, deformed face awash with apprehension, and Sister Argenta was a bit green. His soles resounding on the concrete floor, van Calox walked around the room — prudently, and yet more boldly than any of us would have dared in this den of wickedness. His own small luminator lit sickening gleams over pooled ichor and blood. When he came back to our little group, he was very much his usual self, and when he spoke it was with his usual aloofness.

'I am beginning to get some idea. Those must be the inhabitants of the lower levels — some of them, anyway, as the population would be numbered in millions. The cultists did something to these poor people, and now they are studying the result.'

'But what did they do to them?' Her Ladyship had collected herself now; she once again carried herself with the quiet pride I have grown to value so much, and only someone who knew her well would have glimpsed the uneasiness below.

'Warp sorcery, no doubt. Do not…' Van Calox hesitated. 'It is better not to dwell too much on the particulars, Katov. Even thinking about it might plant the seeds of corruption in your soul.'

Lady Cassia was the next to speak. 'So, Master van Calox, these are people? Monstrously mutated, but still people?'

Ah, her discomfort was palpable, and I understood the reason. During those months on the Emperor's Mercy, lady Cassia has been more exposed to the Creed than she ever was before — both in theory, as we all attend service weekly, and in practice, as she was confronted with the crew and she realised that, in truth, she was a mutant herself. A noble girl entrusted with the high purpose that is hers cannot, of course, compare to the lowlife rabble that sprouts now and then from the lower decks. Try as I might, though, her delicate sensibilities are still often hurt by the assumption of mistrust that rightfully sticks to other, not Emperor-blessed, mutants.

'Yes, lady Cassia,' replied van Calox. 'I have seen many mutants whose features have been distorted under the effects of the Archenemy… but this is something beyond all imagining. Perhaps it is some side effect of a cursed ritual and they were brought here to be studied. Even fallen tech-priests who have rejected the Omnissiah are driven by a perverted hunger for knowledge.'

'Whatever was done to them, it was vile,' spat Her Ladyship.

'It frightens me,' I said. 'Such heresy taking root on a von Valancius world! A single assault was enough for Kiava Gamma to fall. How can we protect other planets from this fate?'

Master van Calox scowled. 'This would be my job, Seneschal. As for your other statement… that single assault must have been the culmination of years, if not decades, of preparations and plots.'

Before I could overcome the indignation of such an accusation over the late lady Theodora's rule, another lament for help came from the mutants' collective throats. Every minute of their existence a torture, and they still struggled against what must be an unending pain in order to speak! More words, threaded in a coherent sentence, that must have taken so much energy and dedication to craft in those long minutes since their last! You promised that we wouldn't suffer! A cry of pure outrage if there ever was any, and we were all brought back from the realm of speculation to the gravity of our present situation. Van Calox's gloved hand rested on the nearest cage; he pondered in silence over something and said slowly: 'Since they still speak, if they remember the people who did this to them… Perhaps a little biomancy will allow us to draw fragments of knowledge out of them and uncover those plots. Unless it will trigger further changes.'

I don't know why I thought to look at Her Ladyship then. She had that half-exasperated expression that often comes right before a scathing remark, and indeed it came straight away.

'What happened to not dwelling too much on the particulars? Oh well. If your soul, unlike mine, is naturally immune to corruption, then you'll have no objection to my abandoning you there to tinker away like a half-witted cogboy. No offence, Pasqal.'

'None taken,' replied the Magos. 'I am under no directives to be offended on my less intelligent tech-comrades' part.'

'One day, Katov, you will wait until the end of a reasoning line before jumping on your high horses,' coolly said van Calox, 'and that will be the day you have a decent chance of not being easily baited at regicide. I was about to add the risks are too high, the chances of reward too low, and that it would only prolong the mutants' suffering.'

Yet when he turned away, I wondered. He had seemed quite sure of himself, musing about biomancy and uncovering plots. Could it be that, under Her Ladyship's influence, he has grown a little more merciful, and caught himself in time for fear of her chastising? Unless her interruption brought him back to his senses before he played with forces best left alone?

With Magos Pasqal's help, we all soon rigged the corrupted cogitators, linked to the cages and the rods, to overload. It was a nasty business. We dared not shut the power down too soon, and those masses of fused limbs twitched and screamed and flailed in spastic rhythm for long minutes. A pungent smell of charred meat mixed with ozone took us at the throat. A flamer, raining burning promethium, would have been better! When, at last, the execution was done — and I felt dirty, tainted by the horror we had culled from the world — there was a heavy silence, and darkness. I hadn't noticed earlier for the noise of cogitators, like insects crawling over glass panels, but here we were cut from the manufactorum's perpetual din. It was oppressive in ways silence has no right to be.