Arcing battlements crowned its immensity, the colossal, mountainous fortress engine unlike anything Kasim had seen before. He had heard the rumours and looked over the technical specs and blueprints of similar machines, but nothing had prepared him for the awesome spectacle of so gargantuan a war machine in the flesh.

Weapons capable of obliterating cities depended from its wide shoulders and its head was a grinning, horned skull of burnished silver.

*Imperator,' said Kasim.

PRINCEPS CAVALERIO SCOURED the Manifold for information, reading nothing through the barking, squealing hash of sc.r.a.pcode fouling the airwaves. He could get nothing from Princeps Sharaq and feared the worst. Mortis was on the march, and Cavalerio wondered if Princeps Camulos was about to make good his threat of a coming storm.

His battle group was marching at flank speed towards their fortress and he could feel the ancient heart of Victorix Magna protest at the demands placed upon it. His own heart beat in time with the great machine and he felt a growing numbness spreading through his limbs.

Cavalerio fought against the sensation, willing both his mortal frame and the immortal might of his engine to keep going.

*Do you really think Mortis is about to attack Ascraeus Mons?' asked Moderati Kuyper.

*I don't know,' confessed Cavalerio, their words spoken through the link of the Manifold. *I believe Camulos wants to drive our Legio from Tharsis, but this seems bold even for him.'

*Then perhaps this is the first strike in a larger war,' suggested Kuyper.

Cavalerio kept his thoughts close, remembering what Camulos had said at the Council of Tharsis.

Sides were being chosen and battle lines drawn all across Mars, and while Cavalerio couldn't bring himself to believe that the t.i.tan orders were about to go to war, this manoeuvre of Mortis seemed deliberately calculated to rouse the ire of Tempestus.

Well, Indias Cavalerio was not about to rise to the bait of this provocation.

*I don't think they will attack,' he said. *I think they want us to attack them, to fire the first shot so as to justify their retaliation.'

*Our warriors will only fire if they're fired on first,' said Kuyper.

Cavalerio thought of the engine commanders at Ascraeus Mons: Sharaq, Lamnos and Kasim. Sharaq could be trusted to understand the situation, but Lamnos and Kasim?

Their hearts were fiery and warlike, as was expected of Warhound drivers, but where heart and mind were in balance in more experienced warriors, Cavalerio feared what impulsive decisions they might make in the heat of the moment.

*Get me Sharaq's battle group,' he said. *I need to make sure they know not to fire first.'

*Understood, Stormlord,' said Kuyper, returning his attention to breaking through the interference.

Cavalerio opened the Manifold link to Magos Argyre. *How long till we reach the Mons?'

*Update: at flank speed, we will be within visual range of Ascraeus Mons in seventeen point four minutes. However, the reactor is running twenty-seven per cent in excess of what I believe it can safely handle at this time.'

*Increase reactor output,' ordered Cavalerio. *I want us there in less than ten.'

*Warning: to increase reactor output beyond the current rate of-'

*I don't want to hear any excuses!' snapped Cavalerio. *Just make it happen!'

THE IMPERATOR t.i.tAN had not come alone.

Two Warlords and a Reaver marched alongside it like the hangers-on of a scholam bully. Kasim could see no sign of a Warhound picket or skitarii escort, but with engines as large as this, what need had they of any skirmish screen?

The ground shook and cracked at its pa.s.sing, and Kasim could only watch in mute awe as the mightiest war machine he had ever seen swept past him like an uprooted hive on mountainous legs.

*What do we do?' breathed Moderati Vorich.

What indeed? To fight such a monster was suicide, but its path would see it cross the Tempest Line in a little over nine minutes, and then they would have to fight it. They would be as ants against a bull-grox... but even ants could bring down a larger beast with enough numbers.

As his now active surveyors gathered what information they could on the might of the Imperator, Kasim knew that Tempestus had not the guns to defeat such a terrifying opponent.

*We follow it,' said Kasim. *And we wait.'

*Wait for what?' asked Vorich.

Kasim looked down at his medallion, again wishing he could touch it. *To see if this is the day we die,' he said.

DALIA SCREAMED AS the howling gale of psychic energy enveloped her, feeling it tear at her like a malicious hurricane. She heard screaming voices that clawed at the inner surfaces of her skull and whispers she could not possibly be hearing, but which sounded as clear as though she heard them lying on her bed in the middle of the night.

White light filled the chamber, the walls blurring in a rippling haze thrown off by the roaring column of silver that flared from the dome's apex and speared down towards Jonas Milus upon his throne.

She heard the metallic ring of the doorway closing behind her and spared a brief thought for Caxton and the others. Her robes billowed in the grip of powerful etheric winds, her skin raw and scoured by invisible energies that pa.s.sed through her skin to the marrow and beyond.

Billowing ghosts of light swarmed the chamber, fleeting unnatural forms that defied description and which lingered uncomfortably in the darkest reaches of her imagination. Clouds of feelings filled the chamber: thunderheads of anger, zephyrs of regret, hailstorms of longing, hurricanes of love and betrayal.

Emotions and meaning surrounded her, though how such concepts could be given physical, visible form was a mystery to her. Dalia took a step into the chamber, feeling her will erode in the face of the primal energies that surrounded her and infused her at the same time.

*Jonas!' she yelled, the words fleeing her mouth in a gush of red. At first she feared it was blood, but the colour in the air vanished almost as soon as it had appeared. The noise filling the chamber was incredible, like the death scream of an entire race or the birth pangs of another.

All emotion and knowledge was here, and Dalia realised that this was the aether; this was the realm beyond the one her senses could consciously perceive. This was the source of all knowledge and the source of the greatest danger imaginable.

This was what she had allowed Jonas Milus to be exposed to.

The thought galvanised her steps, and she forced her way through the maelstrom of light and colour, feeling the energies unleashed by the psykers in the coffered ceiling bleed off as they began to die. She could feel their lives ending, dissipating into the cacophony of light and noise. She wept with sympathetic pain, feeling each death as a splinter of needle-sharp agony in her mind.

Dalia shielded her eyes as she drew closer to the dais, seeing Jonas Milus convulsing upon the throne, illuminated by the blinding light of the Astronomican. His head jerked spasmodically from side to side, his mouth a blur of motion as he screamed and yammered streams of words too fast to be understood.

She pushed her way up the steps towards him, dropping to her knees to better fight against the gales of energy and howling ghosts that swarmed the dais.

*Jonas!' she called, reaching out to him.

She couldn't reach him and crawled, inch by inch, towards him. His screaming was undimmed, the words flooding from him so fast in an ululating howl of pain. Fire blazed in his eyes, crackling with ancient power, the power of something far greater than anything mankind had ever known.

At last Dalia reached the top of the dais and saw that the storm of psychic energy swirled around the throne, yet never touched it, as though some invisible, ant.i.thetical barrier was holding it back.

The throne shone as though illuminated from within by some vast elementally powerful force. Though she and her compatriots had struggled so hard to create it, she now wished they had failed utterly.

She wished to be rid of her gift and the consequences of what it had done.

Even as she formed the thought, her limbs jerked and she rose to her feet in the manner of a marionette lifted by its puppeteer. Dalia cried out as her limbs obeyed the unknown imperatives manipulating her body and she stared into the face of Jonas Milus.

The fire that burned in his eyes spilled outwards to engulf his entire body, pouring over him like blazing mercury. Her screams matched his, and the restraints that had bound him to the throne fell away, unmade by the silver fire that crawled over his flesh like a living thing.

The empath rose from his throne, a living being of illuminated silver with the light of unknown suns burning in his eyes. Dalia could not meet his gaze, fearful that the power there would consume her were she to stare into it for too long. Beneath the inner luminescence that filled his body, she could see his flesh disintegrating like ice before a flame.

*I have seen it!' he hissed, his voice sounding as though echoing from somewhere impossibly distant and deep. *All knowledge.'

*Oh Jonas, I'm sorry.'

*Sorry? No, Dalia, I won't have your pity,' said Jonas, fire writhing in his mouth as he spoke, his voice growing fainter with every word. *I have seen the truth and I am free. I know it all, the Emperor slaying the Dragon of Mars... the grand lie of the red planet and the truth that will shake the galaxy, all forgotten by man in the darkness of the labyrinth of night.'

Jonas Milus stepped towards Dalia, and the psychic winds were pushed away from her as though by his very presence. As he drew closer to her, Dalia heard the whine of great machinery powering down and the thump of closing relays as power to the Akashic reader was finally shut off.

The light of the Astronomican still filled the chamber, and the winds of psychic energy still roared and seethed at its edges, but their power was diminishing. The mundane features of the s.p.a.ce began returning, the marble floor, the sensation of ma.s.s and solidity, the heat of the air and the smell of burned flesh.

*Quickly! Look at me, Dalia,' said Jonas with desperate urgency. *Look at me and know your destiny.'

She forced her head up and stared into the face of Jonas Milus as the light in his eyes was extinguished and the last of his human flesh faded away to oblivion.

The connection lasted the briefest fraction of a second, but that was enough.

Dalia screamed until she had no more breath, and took refuge from horrors that should never be borne by mortal brains in the black sleep of unconsciousness.

PRINCEPS SHARAQ FOLLOWED the inbound tracks on the Manifold. The Imperator t.i.tan was closing fast, surface scans of its ident.i.ty markers revealing its name to be Aquila Ignis, an engine constructed in the Daedalia forge yards far to the south of Tharsis.

Its princeps, if such a vast machine could be commanded by just one man, was making no effort to conceal its power, and Sharaq fed the flow of data being collected on the terrible engine into the gunbox recorders of his war machine.

If the time ever came when they had to fight this engine, it would pay to be prepared.

With the unmasking of the Imperator, the howling binary interference had lifted, the storms that had whipped the dust into the air with such force dissipating as though they had never existed.

The vox crackled as the engines of Tempestus restored communications, each one filling the airwaves with excited chatter at the incredible sight marching towards Ascraeus Mons. Raptoria and Astrus Lux shadowed the Imperator, keeping a safe distance from it and its escorting Warlords.

*Do you have firing solutions to that engine?' asked Sharaq.

*Yes, my princeps,' said Bannan hesitantly. *But if we open fire, it'll vaporise us in an instant. We can't fight something that big.'

The Imperator blotted out everything around it, a walking mountain that impossibly moved closer with thunderous footsteps. Sharaq wished the rest of his Legio were here alongside him.

To be standing directly in the path of such a t.i.tanic creation, a fearsome miracle of construction and innovation, was a prospect no man should have to face alone. Raptoria and Astrus Lux would fight alongside him, and the Skitarii weapons platforms would add their weight of fire, but they would be of little real use when the mighty engines started shooting.

For all intents and purposes, Sharaq was alone... his greatest fear as a princeps.

With Princeps Cavalerio's battle group they would at least have a chance of wounding the beast, and might even best it, but without them...

*Time to the Tempest Line?' asked Sharaq, sweating profusely despite the cool air in the carapace c.o.c.kpit.

*Three minutes, my princeps,' said Dolun.

*Come on, turn away, d.a.m.n you, turn,' hissed Bannan, and Sharaq echoed his sentiment as the seconds ticked by with the inexorably slow slide of thick engine oil.

Then the Manifold crackled and the blessed voice of the Stormlord came over the vox.

*Engines of the Legio Mortis,' said Princeps Cavalerio, his voice stentorian and unequivocal. *You are on course to cross the Tempest Line, whereupon you will be in breach of the Tharsis non-aggression pact as signed by Princeps Acheron of Legio Mortis and Princeps Bakka of Legio Tempestus at the First Council of Cydonia. Turn back now or you may be fired upon.'

Sharaq watched the Manifold as Cavalerio's engines marched up through the western pallidus, billowing clouds of dust swirling in their wakes. To have reached Ascraeus Mons in such time must have torn the hearts from their reactors, but they were here and that was what mattered.

*Engines of Legio Mortis respond immediately!' demanded Cavalerio, and Sharaq could hear the strain in the Stormlord's voice. He checked the Manifold, getting elevated biometric and reactor readings from the Victorix Magna.

The thunderous form of the Imperator did not slow and Sharaq saw that it was moments from crossing the Tempest Line, whereupon it would be in the territory of Legio Tempestus. His mouth was dry and he took a sip from the hydration straw at his cheek.

*Legio Mortis, respond!' demanded Cavalerio, and Sharaq's heart swelled with pride as the stately form of Victorix Magna marched to stand alongside Metallus Cebrenia, firm in the path of the colossal Imperator.

*Fifteen seconds to the Tempest Line,' warned Moderati Bannan.

Tharsis Hastatus, Arcadia Fortis and Vulpus Rex took position alongside Cavalerio's engine, and the entire strength of Legio Tempestus on Mars stood before the mightiest war engines of Legio Mortis.

*This is your final warning. Mortis!' bellowed Cavalerio.

Dreadful terror settled in Sharaq's gut as Moderati Bannan said, *Tempest Line breached, my princeps.'

SYSTEMAE MECHANIc.u.m.

2.01.

THE TEMPEST LINE had been breached. The sovereign territory of one of the most honourable Legios of Mars had been violated. Armed engines had blatantly marched from their fortress and come with warlike intent to another. Despite the evidence before him, Princeps Cavalerio still could not accept that Mortis wanted to exchange fire.

Why would they risk such a thing? Supporting Horus Lupercal and engaging in provocation was one thing, but daring another Legio to fire upon your engines made no sense unless there was a darker, more far-reaching scheme at work.

If battle were joined here, little would survive, and even with the Imperator, Mortis would not walk away unscathed.

Cavalerio had always suspected that Camulos was a man unsuited for command, and this confrontation seemed only to confirm his suspicions. It was madness, and Cavalerio did not want to be sucked into that madness. The factions of the Mechanic.u.m might make war on one another, but the t.i.tan Legions were supposed to be above such things, to hold the ideals of a united Mars and Terra above all things, even their own differences.

*My princeps,' said Moderati Kuyper. *The Tempest Line.'

*I know,' said Cavalerio. *Should we open fire?'

*You have a solution?'

*At this range we don't need one,' Kuyper a.s.sured him. *That monster's so large we won't miss.'