Without those reactors, it would become increasingly difficult to keep the engines of his beloved Legio operational. Whoever had struck at Maximal had done so with great precision, destroying the reactor that provided the most power to the Tempestus fortress within Ascraeus Mons.

Cavalerio reclined in a contoured couch, his arms and skull sheathed in cables and haptic implants that burrowed beneath his skin like silver worms. This arrangement of a physical connection was fast becoming obsolete, a means of command seen as archaic by some princeps of Mars. Many were already embracing full body immersion in an amniotic tank that allowed information to flow like liquid through a virtual world, but Cavalerio much preferred an actual connection with the engine he commanded.

He knew the gradual atrophy of his body meant that he would soon have no choice but to accept emplacement within such a tank, for he could not endure the pain and stress, both mental and physical, of too many more separations.

That day was not yet here, and Cavalerio pushed the thought from his mind as he concentrated on the mission at hand.

Linked with the Manifold, Cavalerio saw the world around him as though the mighty structure of Victorix Magna were his own flesh and blood. The barren, cratered landscape of Mars stretched out all around him, the pale, ashen wastelands of the pallidus to the southwest and the tumbled rockfaces of the twin craters upon which Maximal's forge hunched like a collection of blistered towers.

Ahead, the tumbled, haphazard sprawl of the Gigas Sulci sub-hives filled the landscape, a wretched, sweltering collection of towers, habs and shanties that housed the millions of workers who toiled in the Fabricator General's manufactorum upon the towering, lightning-wracked slopes of Olympus Mons.

For days Kelbor-Hal's domain had been wreathed in seething thunderheads, the slopes and forges hammered by crackling bolts of purple lightning. Cavalerio didn't know what manner of experimental work the Fabricator General had going on, but it was creating some lousy atmospherics and interfering with vox-traffic for thousands of kilometres in all directions.

Every channel was alive with sc.r.a.ppy blurts of code that sounded like a chorus of urgent voices crowded into a single frequency. Cavalerio had been forced to mute the volume on the vox, the chattering nonsense code giving him a splitting headache.

Cavalerio put the Fabricator General from his mind and cast his augmented gaze far to the south, where thick clouds from the refinery fields of the Daedalia Planum smothered the landscape, smudging the horizon in permanent crepuscular gloom.

The three cobalt blue engines in Cavalerio's battle group marched at a steady pace along the borders between the territory of the Fabricator General and that of Ipluvien Maximal, striding like three great giants of legend.

On Cavalerio's left was the stately Warlord, Tharsis Hastatus, commanded by his comrade-in-arms, Princeps Suzak. Hastatus was a killing engine and Suzak a man who could be depended upon to deliver a lethal strike when it was needed most.

To his right, the Reaver Arcadia Fortis marched with eager steps, pulling slightly ahead of the main group. Its princeps, Ian Mordant, was a fiery-hearted hunter, a warrior recently promoted from a Warhound princepture who hadn't yet shed his preference for lone wolf operations.

*Close it up, Mordant,' said Cavalerio. *My sensori tells me the ground here is soft and that some of the sand has shifted over the chasms. I don't want to have to call out a bulk lifter crew to lift your engine off its a.r.s.e.'

*Understood,' came the terse reply, screeches and howls of interference scratching over Mordant's voice. Mordant was still getting used to the quirks of his new command, he and his engine still gauging the measure of the other, and his responses were typically brusque. Cavalerio only tolerated such behaviour because Mordant was one of his best warriors, with a kill tally only exceeded by his own.

*Still thinks he's a Warhound driver, eh?' said Kuyper, the Magna's moderati.

*Indeed,' agreed Cavalerio. *The Arcadia will soon cure him of that, she's a stern mistress that's for sure. Any word from Basek?'

*Nothing yet, my princeps,' said Kuyper, consulting the vox-log.

*Sensori, do you have a fix on Vulpus Rex?'

*I think so, my princeps,' answered Palus, *but these d.a.m.ned atmospherics are making it hard to keep a fix on their return. And our old girl's vision's not what it used to be.'

*That's not good enough, Palus,' cautioned Cavalerio. *Find her. Now.'

*Yes, my princeps,' answered Palus.

Cavalerio gave his sensori a few moments before asking, *Do you have her now?'

*She's further south,' answered Palus with a measure of relief, *skulking around the edge of the Gigas sub-hives at the end of the Barium Highway.'

*Good ambush site,' noted Kuyper. *If anything's going to come up on us, it'll be from there.'

*And they'll find Basek waiting for them,' added Lacus the steersman with relish.

Cavalerio nodded. Princeps Basek commanded Vulpus Rex, the finest Warhound t.i.tan of Legio Tempestus, a fleet killer of engines far larger than its hunched feral size would suggest.

Pulling up the schematics of the surrounding landscape from the Manifold and meshing them with the topographical view afforded him through the t.i.tan's senses, Cavalerio saw that Kuyper's a.s.sessment was correct. Only the Barium Highway was wide enough to allow an engine to pa.s.s without demolishing half the dwellings.

The confused tangles of glowing outlines that depicted the edges of the sub-hives were, however, outdated and likely to be inaccurate, so it never paid to be complacent where the safety of an engine was concerned. So much was built or demolished that most maps of the sub-hives were rendered obsolete on a daily basis.

*Bring us about on a heading of two-two-five,' ordered Cavalerio, feeling his muscles twitch as the mighty form of Victorix Magna swung about and began a stately march along the edge of Maximal's domain. *Magos Argyre, what's our reactor status?'

*a.s.sessment: borderline,' said Argyre, the t.i.tan's enginseer, who stood immobile in his rear-mounted compartment behind the princeps' dais. *We should not have marched, Princeps Cavalerio. The reactor's spirit is troubled and it is dangerous to walk without having recited the full litany of calming prayers to soothe its troubled heart.'

*So noted, Magos,' said Cavalerio. *Bring us to slow march speed.'

*Slow march speed,' repeated Argyre.

Cavalerio monitored their surroundings through the depths of the Manifold, drinking in data from pressure sensors, atmospheric samplers, infrared panels and microwave receptors. His understanding of the world around him was unparalleled, his awareness unmatched by any other ent.i.ty on the plains of Mars.

He tried to keep his attention focused on the ground before him, for the landscape around Maximal's forge was treacherous, but he found his attention continually drawn to the ugly, bruised skies above Olympus Mons.

*What are you up to, Kelbor-Hal?' he muttered.

*My princeps?' asked Kuyper.

*Hmmm? Oh, nothing, I was just wondering out loud,' replied Cavalerio.

Kuyper had caught his interest in Olympus Mons, their communal link to the Manifold allowing no secrets to exist between them.

*It's the Grand Mountain, isn't it?' asked Kuyper, using the t.i.tan drivers' old name for Olympus Mons. The moderati of Victorix Magna twisted in the reclined couch at the Warlord's chin mount to face Cavalerio. *She frets about something.'

*The Grand Mountain,' agreed Cavalerio. *She speaks with the voice of Mars and something troubles her.'

*My princeps!' called Sensori Palus. *Vox contact from Ascraeus Mons. Princeps Sharaq urgently requests to speak with you.'

*On the Manifold,' ordered Cavalerio.

A ghostly hash of green light swam into focus before the reclining princeps, a holographic image of Princeps Sharaq standing in the Chamber of the First. The image jittered like a jammed signal, the words fading in and out as though the code was somehow corrupt.

*What is it, Sharaq?' demanded Cavalerio. *We are on-mission.'

*I know, Stormlord, but you must return to Ascraeus Mons immediately.'

*Return? Why?'

Sharaq's answer was blotted out by a squealing blurt of code like an animalistic bellow of rage, his image distorting as if in the grip of a rippling heat haze.

*...Mortis. They march!'

*What? Repeat last,' snapped Cavalerio.

Sharaq's image suddenly sharpened, and Cavalerio heard the next words as clearly as if his fellow princeps had been standing before him.

*Legio Mortis,' repeated Sharaq. *Their engines walk. And they are heading towards Ascraeus Mons.'

1.08.

DALIA STARED IN fascination at Ipluvien Maximal, wondering how much of him was mechanical and how much was human. From the little she could see of his body beneath the coolant robes he wore to preserve the integrity of the machine parts of his body, the answer was not much. There was precious little left of the magos that spoke of their shared racial kinship.

*You have never seen an adept of the Mechanic.u.m like me?' asked Maximal.

*No,' said Dalia. *Most of the ones I've seen still look human. You sound human, but you don't look it.'

Maximal turned to Adept Zeth and blurted a crackling burst of code, the viewscreens attached to his host of mechadendrites flashing with his amus.e.m.e.nt.

*Oh, I'm sorry,' said Dalia. *I didn't mean to speak out of turn, I was just curious.'

The robed magos turned back to her. *You understand binaric code? Without modifications?'

*I've picked it up,' said Dalia, embarra.s.sed at the scrutiny.

Maximal nodded his oblong, helmeted head, the whirring lenses adjusting to better view Dalia. *You were right, Zeth, she is quite remarkable. Perhaps this project of yours might actually bear fruit after all.'

Dalia looked past the hulking form of Maximal to the wide window that looked out into the domed chamber where Jonas Milus was strapped to the theta-wave enhancer, beneath the sightless eyes of the thousands of psykers encased in the coffers of the dome.

*It will work, I'm sure of it,' whispered Dalia.

*Let us hope so, young Dalia,' said Maximal. *A great deal depends upon it.'

*You have a lovely voice,' said Dalia. *It's rich, like a well-spoken man of the Romanii. Why would you bother with a voice like that when you look like you do?'

*We all have our foibles, Dalia,' explained Maximal. *This voice belonged to a great singer of operatic verse and the sounds remind me of all that is good in mankind.'

Dalia didn't know what to say to that, so returned her attention to the view beyond the armoured gla.s.s that was all that separated the control room from what was about to happen.

An army of calculus-logi attended to a bewildering bank of cogitators and logic engines that controlled aspects of the Akashic reader she had not known about. Many of the symbols on the panels were unknown to her or used words she didn't know. The control room was a thrumming box of tension and activity, the sense of something great and portentous heavy on everyone's features.

Even the servitors looked tense, though Dalia told herself that it was just her imagination.

*When does it start?' asked Dalia, turning to her colleagues.

Caxton and Severine shrugged and even Mellicin had no answer.

*It starts now, Dalia,' said Adept Zeth appearing at her side and placing a bronze gauntlet on her shoulder. *All of this is down to you.'

*Then let's just hope it works,' said Dalia, looking at the distant, serene features of Jonas Milus.

*Terran horizon clear,' said an automated voice. *Astronomican light readings approaching test window parameters. Alignment on track.'

*Removing pentobarbital wards from psychic foci,' said the toneless voice of a calculus-logi. *Increasing aperture of pineal antenna.'

*Magma generators diverting power to collectors.'

*What do all those things mean?' asked Dalia.

*You remember I told you that it takes a great deal of energy to breach the walls separating us from the aether?' said Zeth.

*Yes.'

*Well, it takes a form and amount of energy that cannot be generated here on Mars.'

*What kind of energy?'

*Psychic energy,' said Zeth, *in quant.i.ties that can only be harvested from one source, the Astronomican.'

*The Emperor's warp beacon? The one that guides starships?'

*The very same,' said Zeth, pointing towards the metallic disc at the dome's apex, from which golden spears of energy were arcing. *Only the Astronomican has the required psychic energy that will allow the Akashic reader to access the sum of all knowledge we seek. We will divert a fraction of its power into the chamber to empower the psykers and open the gates to the aether.'

*Won't it disrupt the Astronomican if we use its power?' asked Dalia.

Zeth looked over at Maximal, a moment's hesitation giving Dalia the answer she sought.

*It will,' admitted Zeth, *but only for a short span of time.'

Dalia stepped towards the consoles that operated the Akashic reader, a.s.similating what Zeth had just told her into her understanding of what was being said and what the words carved into the wooden panels meant.

She had no real idea of how powerful the Astronomican was, but understood that even a fraction of its energy would be greater than anything she could imagine. She looked into the chamber at the waking psykers and knew with sudden, awful, clarity that she had overlooked something.

*How are you going to divert the Astronomican's power?' she asked.

*Mars will be in alignment with Terra soon and we will pa.s.s through the radiance of the psychic beacon. The pineal antennae will collect the energy and divert it to the psykers.'

*Is that how you've always done it?' asked Dalia urgently.

Adept Zeth shook her head. *No. This will be the first time we have pa.s.sed through the Astronomican.'

*Oh no,' whispered Dalia. *The calculations are wrong. They're all wrong!'

*Wrong, what are you talking about?' demanded Adept Maximal.

*The energy readings,' said Dalia. *I understand now... the different readings. Fluctuating maximums and minimums. Apogee and perigee... That's why the numbers were different. We a.s.sumed a baseline average, but that's not what we're going to get now.'

*Dalia, explain yourself,' said Zeth. *Talk me through your concerns.'