The Dies Irae swung to the side, its immense foot taking the roofs from a tangle of bunkers and shattering artillery emplacements as it crashed forwards. A scrum of Isstvanian soldiers scrambled from the ruins, setting up heavy weapons to pour fire into the t.i.tan as it towered over them.

The Isstvanians were well-drilled and well-armed, and though the majority of their weapons weren't the equal of a lasgun, trenches were a great leveler and a man with a rifle was a man with a rifle when the gunfire started.

The Death Guard slaughtered thousands of them as they bludgeoned their way through the trenches, but the Isstvanians were more numerous and they hadn't run. Instead they had fallen back trench by trench, rolling away from the relentless advance of the Death Guard.

The Isstvanians, with their drab green-grey helmets and mud-spattered flak-suits, were hard to pick out against the mud and rabble with the naked eye, but the sensors on the Dies Irae projected a sharp-edged image onto Ca.s.sar's retina that picked them out in wondrously clear detail.

Ca.s.sar fired a blast of ma.s.sive-caliber sh.e.l.ls, watching as columns of mud and bodies sprayed into the air like splashes in water. The Isstvanians disappeared, destroyed by the hand of the Emperor. *Enemy forces ma.s.sing to the port forward quadrant,' said Moderati Aruken.

To Ca.s.sar his voice felt distant, though he was just across the command bridge of the t.i.tan.

*The Death Guard can handle them,' replied Turnet. *Concentrate on the artillery. That can hurt us.' Below Ca.s.sar, the gunmetal forms of the Death Guard glinted around the bunkers as two squads of them threw grenades through the gun ports and kicked down the doors, spraying the Isstvanians who still lived inside with bolter fire or incinerating them with sheets of fire from their flamers. From the head of the Dies Irae, the Death Guard looked like a swarm of beetles, with the carapaces of their power armour scuttling through the trenches.

A few Death Guard lay where they had fallen, cut down by artillery fire or the ma.s.sed guns of the Isstvanian troops, but they were few compared to the Isstvanian corpses strewn at every intersection of trenches. Metre by metre the defenders were being driven towards the northernmost extent of the trenches, and when they reached the white marble of a tall Basilica with a spire shaped like a trident, they would be trapped and slaughtered.

Ca.s.sar shifted the weapon arm of the Dies Irae to aim at a booming artillery position some five hundred metres away, as it belched tongues of flame and threw explosive sh.e.l.ls towards the Death Guard lines.

*Princeps!' called Ca.s.sar. *Enemy artillery moving up on the eastern quadrant.'

Turnet didn't answer him, too intent on something being said to him on his personal command channel. The princeps nodded at whatever order he had just received and shouted, *Halt! Aruken, cease the stride pattern. Ca.s.sar, shut off the ammunition feed.'

Ca.s.sar instinctively switched off the cycling of the weapon that thundered from the t.i.tan's arm and the shock forced his consciousness back to the command bridge. He no longer looked through the eyes of the Dies Irae, but was back with his fellow officers.

*Princeps?' asked Ca.s.sar, scanning the readouts. *Is there a malfunction? If there is, I'm not seeing it. The primary systems are reading fine.'

*It's not a malfunction,' replied Turnet sharply. Ca.s.sar looked up from information scrolling across his vision in unfocused columns.

*Moderati Ca.s.sar,' barked Turnet. *How's our weapon temperature?'

*Acceptable,' said Ca.s.sar. *I was going to push it on that artillery.'

*Close up the coolant ducts and seal the magazine feeds as soon as possible,'

*Princeps?' said Ca.s.sar in confusion. *That will leave us unarmed.'

*I know that,' replied Turnet, as though to a simpleton. *Do it. Aruken, I need us sealed.'

*Sealed, sir?' asked Aruken, sounding as confused as Ca.s.sar felt.

*Yes, sealed. We have to be airtight from top to bottom,' said Turnet, opening a channel to the rest of the mighty war machine's crew.

*All crew, this is Princeps Turnet. Adopt emergency biohazard posts, right now. The bulkheads are being sealed. Shut off the reactor vents and be prepared for power down.'

*Princeps,' said Aruken urgently. *Is it a biological weapon? Atomics?'

*The Isstvanians have a weapon we didn't know about,' replied Turnet, but Ca.s.sar could tell he was lying. *They're launching it soon. We have to lock down or we'll be caught in it.'

Ca.s.sar looked down at the trenches through the t.i.tan's eyes. The Death Guard were still advancing through the trenches and bunker ruins. *But princeps, the Astartes-'

*You have your orders, Moderati Ca.s.sar,' shouted Turnet, *and you will follow them. Seal us up, every vent, every hatch or we die.'

Ca.s.sar willed the Dies Irae to shut its hatches and seal all its entranceways, his reluctance making the procedures sluggish.

On the ground below, he watched the Death Guard continue to grind their way through the Choral City's defenses, apparently unconcerned that the Isstvanians were about to launch Throne knew what at them, or unaware. As the battle raged on, the Dies Irae fell silent.

THE MAIN AUDIENCE chamber of the Vengeful Spirit was a colossal, columned chamber with walls of marble and pilasters of solid gold. Its magnificence was like nothing Sindermann had ever seen, and the thousands of remembrancers who filled the chamber wore the expressions of awed children who had been shown some new, unheard of wonder. Seeing many familiar faces, Sindermann guessed that the fleet's entire complement of remembrancers was present for the Warmaster's announcement.

The Warmaster and Maloghurst stood on a raised podium at the far end of the hall, too far away for either of them to recognize Sindermann, Mersadie or Euphrati.

Or at least he hoped so. Who knew how sharp an Astartes eyesight was, let alone a primarch's?

Both Astartes were wrapped in cream robes edged in gold and silver and a detail of warriors stood beside them. A number of large pict screens and been hung from the walls.

*It looks like an iterators' rally on a compliant world,' said Mersadie, echoing his own thoughts So similar was it that he began to wonder what message was to be imparted and how it would be reinforced. He looked around for plants in the audience who would clap and cheer at precise points to direct the crowd in the desired manner. Each of the screens displayed a slice of Isstvan III, set against a black backdrop scattered with bright silver specks of the Warmaster's fleet.

*Euphrati,' said Mersadie as they made their way through the crowds of remembrancers. *Remember how I said that this was a bad idea?'

*Yes?' said Euphrati, her face creased in a wide, innocent smile.

*Well, now I think that this was a really bad idea. I mean, look at the number of Astartes here.'

Sindermann followed Mersadie's gaze, already starting to sweat at the sight of so many armed warriors surrounding them. If even one of them recognized their faces, it was all over.

*We have to see,' said Euphrati, turning and grabbing his sleeve. *You have to see.'

Sindermann felt the heat of her touch and saw the fire behind her eyes, like thunder before a storm and he realized with a start, that he was a little afraid of Euphrati. The crowd milled in eager impatience and Sindermann kept his face turned from the Astartes staring into the middle of the audience chamber.

Euphrati squeezed Mersadie's hand as the pict screens leapt to life and a gasp went up from the a.s.sembled remembrancers as they saw the b.l.o.o.d.y streets of the Choral City. Clearly shot from an aircraft, the images filled the giant pict screens and Sindermann felt his gorge rise at the sight of so much butchery.

He remembered the carnage of the Whisperheads and reminded himself that this was what the Astartes had been created to do, but the sheer visceral nature of that reality was something he knew he would never get used to. Bodies filled the streets and arterial gore covered almost every surface as though the heavens had rained blood.

*You remembrancers say you want to see war,' said Horus, his voice easily carrying to the furthest corners of the hall. *Well, this is it.'

Sindermann watched as the image shifted on the screen, pulling back and panning up through the sky and into the dark, star-spattered heavens above.

Burning spears of light fell towards the battle below.

*What are those?' asked Mersadie.

*They're bombs,' said Sindermann in horrified disbelief. *The planet is being bombarded.'

*And so it begins,' said Euphrati.

THE PLAZA WAS a truly horrendous sight, ankle-deep in blood and strewn with thousands upon thousands of bodies. Most were blown open by bolter rounds, but many had been hacked down with chainblades or otherwise torn limb from limb.

Tarvitz hurried towards the makeshift strongpoint at its centre, the battlements formed from carved up bodies heaped between the battered forms of fallen drop-pods.

A World Eater with blood-soaked armour and a scarred face nodded to him as he climbed the gruesome ramp of bodies. The warrior's armour was so drenched in blood that Tarvitz wondered for a moment why he hadn't just painted himself red to begin with. *Captain Ehrlen,' said Tarvitz. *Where is he?' The warrior wasted no breath on words and simply jerked a thumb in the direction of a warrior with dozens of fluttering oath papers hanging from his breastplate. Tarvitz nodded his thanks and set off through the strongpoint. He pa.s.sed wounded Astartes who were tended by an apothecary who looked as if he had fought as hard as any of his patients. Beside him lay two fallen World Eaters, their bodies unceremoniously dumped out of the way.

Ehrlen looked up as Tarvitz approached. The captain's face had been badly burned in some previous battle and his axe was clotted with so much blood that it better resembled a club.

*Looks like the Emperor's Children have sent us reinforcements!' shouted Ehrlen, to grunts of laughter from his fellow World Eaters. *One whole warrior! We are blessed, the enemy will run away for sure.'

*Captain,' said Tarvitz, joining Ehrlen at the barricade of Isstvanian dead. *My name is Captain Saul Tarvitz and I'm here to warn you that you have to get your squads into cover.'

*Into cover? Unacceptable,' said Ehrlen, nodding towards the far side of the plaza. Shapes moved in their windows and between the mansions. *They're regrouping. If we move now they will overwhelm us.'

*The Isstvanians have a bio-weapon,' said Tarvitz, knowing a lie was the only way to convince the World Eaters. *They're going to fire it. It'll kill everyone and everything in the Choral City.'

*They're going to destroy their own capital? I thought this place was some kind of church? Holy to them?'

*They've shown how much they value their own,' replied Tarvitz quickly, indicating the heaps of dead in front of them. *They'll sacrifice this city to kill us. Driving us from their planet is worth more to them than this city.'

*So you would have us abandon this position?' demanded Ehrlen, as if Tarvitz had personally insulted his honour. *How do you know all this?'

*I just got here from orbit. The weapon has already been unleashed. If you're above ground when the virus strike hits you will die. If you believe nothing else, believe that.'

*Then where do you suggest we move to?'

*Just to the west of this position, captain,' said Tarvitz, stealing a glance at the sky. *The edge of the trench system is thick with bunkers, blast proof shelters. If you get your men into them, they should be safe.'

*Should be?' snapped Ehrlen. *That's the best you can offer me?'

Ehrlen stared at Tarvitz for a moment. *If you are wrong the blood of my warriors will be on your hands and I will kill you for their deaths.'

*I understand that, captain,' urged Tarvitz, *but we don't have much time.'

*Very well, Captain Tarvitz,' said Ehrlen. *Sergeant Fleiste, left flank! Sergeant Wronde, right! World Eaters, general advance to the west, blades out!'

The World Eaters drew their chainaxes and swords. The bloodstained a.s.sault units hurried to the front and stepped over the makeshift barricades of corpses.

*Are you coming, Tarvitz?' asked Ehrlen.

Tarvitz nodded, drawing his broadsword and following the World Eaters into the plaza.

Although they were fellow Astartes, he knew he was a stranger among them as they ran, spitting battle curses and splashing through the dead towards the potential safety of the bunkers.

Tarvitz glanced up at the gathering clouds and felt his chest tighten.

The first burning streaks were falling towards the city.

*IT'S STARTED,' said Loken.

Lachost looked up from the field vox. Fire was streaking through the sky towards the Choral City. Loken tried to judge the angle and speed of the falling darts of fire a some of them would come down between the spires of the Sirenhold, just like the Sons of Horus's own drop-pods had done hours earlier, and they would hit in a matter of minutes.

*Did Lucius say anything else?'

*No,' said Lachost. *Some bio-weapon. That was all. It sounded like he ran into a fire fight.'

*Tarik,' shouted Loken. *We need to get into cover, now. Beneath the Sirenhold.'

*Will that be enough?'

*If they dug their catacombs deep enough, then maybe.'

*And if not?'

*From what Lucius said, we'll die.'

*Then we'd better get a move on.'

Loken turned to the Sons of Horus advancing around him. *Incoming! Get to the Sirenhold and head down! Now!'

The closest spire of the Sirenhold was a towering monstrosity of grotesque writhing figures and leering gargoyle faces, a vision taken from some ancient h.e.l.l of Isstvan's myths. The Sons of Horus broke their advance formation and ran towards it.

Loken heard the distinctive boom of an airborne detonation high above the city and pushed himself harder as he entered the darkness of the tomb-spire. Inside, it was dark and ugly, the floor paved with tortured, half-human figures who reached up with stone hands, as if through the bars of a cage.

*There's a way down,' said Torgaddon. Loken followed as Astartes ran towards the catacomb entrance, a huge monstrous stone head with a pa.s.sageway leading down its throat.

As the darkness closed around him, Loken heard a familiar sound drifting from beyond the walls of the Sirenhold.

It was screaming.

It was the song of the Choral City's death.

THE FIRST VIRUS bombs detonated high above the Choral City, the huge explosions spreading the deadly payloads far and wide into the atmosphere. Designed to kill every living thing on the surface of a planet, the viral strains released on Isstvan III were the most efficient killers in the Warmaster's a.r.s.enal. The bombs had a high enough yield to murder the planet a hundred times over and were set to burst at numerous differing alt.i.tudes and locations across the surface of the planet.

The virus leapt through forests and plains, sweeping along algal blooms and riding air currents across the globe. It crossed mountains, forded rivers, burrowed through glaciers. The Imperium's deadliest weapons, the Emperor himself had been loath to use them.

The bombs fell all across Isstvan III, but most of all, they fell on the Choral City.

THE WORLD EATERS were the furthest from cover and suffered the worst of the initial bombardment. Some had reached the safety of the bunkers, but many more had not. Warriors fell to their knees as the virus penetrated their armoured bodies, deadly corrosive agents laced into the viral structure of the weapons dissolving exposed pipes and armour joints, or finding their way inside through battle damage.

Astartes screamed. The sound was all the more shocking for its very existence rather than for the horror of its tone. The virus broke down cellular bonds at the molecular level and its victims literally dissolved into a soup of rancid meat within minutes of exposure, leaving little but sloshing suits of rotted armour. Even many of those who reached the safety of the sealed bunkers died in agony as they shut the doors only to find they had brought the lethal virus inside with them.

The virus spread through the civilian populace of Isstvan III at the speed of thought, leaping from victim to victim in the time it took to breathe in its foul contagion. People dropped where they stood, the flesh sloughing from their skeletons as their nervous systems collapsed and their bones turned to the consistency of jelly.

Bright explosions fed the viral feast, perpetuating the fatal reactions of corruption. The very lethality of the virus was its own worst enemy, for without a host organism to carry it from victim to victim, the virus quickly consumed itself.

However, the bombardment from orbit was unrelenting, smothering the entire planet in a precisely targeted array of overlapping fire plans that ensured that nothing would escape the virus.

Entire kingdoms and va.s.sal states across the surface were obliterated in minutes. Ancient cultures that had survived Old Night and endured the horror of invasion a dozen times over fell without even knowing why, millions dying in screaming agony as their bodies betrayed them and fell apart, reducing them to rotted, decaying matter.

SINDERMANN WATCHED THE bloom of darkness spread across the slice of the planet visible on the giant pict screens. It spread in a wide black ring, eating its way across the surface of the planet with astonishing speed, leaving grey desolation behind it. Another wave of corruption crept in from another part of the surface, the two dark ma.s.ses meeting and continuing to spread like the symptom of a horrible disease. *What... what is it?' whispered Mersadie. *You have already seen it,' said Euphrati. *The Emperor showed you, through me. It is death.'

Sindermann's stomach lurched as he remembered the hideous vision of decay, his flesh disintegrating before him and black corruption consuming everything around him. That was what was happening on Isstvan III. This was the betrayal.

Sindermann felt as though the blood had drained from him. An entire world was bathed in the immensity of death. He felt an echo of the fear it brought to the people of Isstvan III, and that fear, multiplied across all those billions of people was beyond his comprehension.