The shields of the Reaver targeted by both Tempestus engines flickered out, worn down by the constant barrage and shut off before they blew out. An instant later the Warlord Tharsis Hastatus, which had been waiting for just that moment, unleashed a punishing volley from its volcano cannon. A searing beam of nuclear fire punched through the Reaver's cockpit, and blew off its entire upper section in a spectacular explosion that hurled pieces of wreckage for over six kilometres.

The thunderous death of the Reaver had been bought by a furious concentration of fire, but that in turn had allowed the second Reaver to close virtually unmolested. Its heavy guns had brought the shields of Arcadia Fortis to breaking point and it was the work of moments to finish the job of overloading them.

A lucky strike on one of the carapace emitters blew out the relays connected to the neural network of the Tempestus engine, and the feedback agonies burned out the cerebral cortex of Princeps Mordant as surely as though he had taken a bolt-round to the head. Arcadia Fortis died with him, the mighty engine grinding to a halt, helpless and utterly at the mercy of its foes.

Basek attempted to flee from the screaming Reaver, its weakened shields and depleted ammunition load no match for such a towering foe. Vulpus Rex moved with grace and speed, but in the face of an indiscriminate barrage of missiles it had no chance of evasion. Missiles slammed into the ground, tearing huge craters and hurling chunks of debris into the air.

Her terrain-reading auspex overloaded with screaming, scrapcode interference, Vulpus Rex tumbled into a crater, one of its weapon arms snapping off and its legs buckling as it landed awkwardly. Trapped and with no escape, Princeps Basek tried to eject, but a brutal volley from the Reaver tore his floundering engine to pieces, killing him and all his crew in a mercifully swift thunder of hard rounds.

Then the sky broke open and the gathering darkness was banished as a bright sunset of atomic detonation painted the distant heavens with fire.

Adept Koriel Zeth closed her eyes at the sight of the fire in the sky, knowing exactly what it represented and feeling the human portion of her body fill with sadness. She focused the Chamber of Vesta's viewing screens to the north and increased the magnification to maximum, knowing what she would see, but dreading it all the same.

All along Ipluvien Maximal's reactor chain of Ulysses Fossae, a score of fiery mushroom clouds climbed skyward. A blast wave of unimaginable force flattened the landscape for hundreds of kilometres bare of life, and the following firestorm would turn the Martian desert to irradiated glass for ten thousand years.

'Goodbye, Ipluvien,' said Zeth, before turning her attention to the unfolding conflict around her own forge, the burnished plates showing such ferocious scenes of battle that even she could scarce believe such slaughter was happening on Mars.

The charge of the Knights of Taranis had cleaved a bloody path through the attackers on the causeway, but their numbers were dwindling fast. Another two Knights had gone down, leaving only Verticorda, Caturix and three warriors.

Every second brought them closer to Melgator's pavilion, but she had no idea whether they would reach it alive. Even if they did, there would be no escape from the heart of the enemy army. Legio Tempestus were fighting a battle that would enter the annals of their histories as one of their most noble, were there any left alive to record it, and her own warriors had fought harder than she could ever have wished.

Kelbor-Hal's minions would suffer greatly to take the Magma City, and unless Zeth acted now, they would take it, that was certain. And not just the Magma City, but the rest of Mars would soon be in the thrall of those loyal to the Fabricator General.

The time had come to follow Ipluvien Maximal's noble action.

Zeth turned from the screens and walked towards the wide shaft that descended into the depths of her forge, bathing in the heat and waves of energy that rippled upwards from the magma far below.

A primitive-looking servitor swathed in a hooded robe followed her, its crudity quite at odds with the sophistication of the chamber. The anonymous cyborg creature took up position alongside Zeth as a dozen slender silver columns rose from the floor around the shaft.

Each of the columns was topped with an intricate arrangement of plugs and Zeth stepped into the middle of them. She reached out and slipped her hands into the biometric readers atop two of the columns, extruding a series of mechadendrites from the length of her spine.

These waved through the air and made contact with the remaining columns, and she began exloading a series of macroinstructions into the noospheric network of the Magma City. A glowing schematic of her forge flickered into life before her, invisible to anyone not noospherically modified.

'I hope Kane managed to rescue at least a portion of his noospheric network from Mondus Occulum,' she whispered to herself. 'It would be a shame for my technology to be forgotten in this sordid civil war.'

'Even facing destruction you are vain,' said a voice behind her.

Zeth turned, unsurprised to see the sinuous form of Melgator's tech-priest assassin slithering through the air behind her.

'I had a feeling I'd be seeing you again,' said Zeth.

'The Cydonian Sisterhood do not forget those who insult us,' said Remiare.

'I'd ask how you got in here, but I have a feeling it won't matter.'

'No,' agreed Remiare. 'It will not.'

The assassin skimmed slowly over the floor of the chamber towards Zeth, drawing a pair of exquisite golden pistols from her thigh sheaths.

'My employer wishes this city captured intact,' said Remiare, inloading to the noospheric map floating before Zeth. 'So you need to stop what you are doing.'

'I'm not going to do that,' stated Zeth.

'I wasn't asking,' said Remiare, and shot Zeth twice in the chest.

Lord Commander Verticorda felt the pain of a dozen wounds through the Manifold of Ares Lictor. His shields were gone and his carapace was cracked in multiple locations. He could barely feel his left arm and the knee joint that had been healed two centuries ago by the touch of the Emperor ached with psycho-stigmatic pain.

All around him he could see the red-lit legions of his enemy surrounding him. Weapons fire spanked from his disintegrating carapace and his fear was not that he was going to die, but that a machine touched by the hand of the Omnissiah would fall into the hands of his enemies.

To his left he saw a group of dark-robed skitarii on one of the causeway's overhanging platforms aim a battery of quad-barrelled guns. He turned his right cannon on them, letting Ares Lictor target them. He felt the thrill of acquisition course down his arm and opened fire, the hurricane of shells obliterating the platform and turning the guns and their operators into an expanding cloud of shredded meat and metal.

Alongside him, Caturix crushed and sliced into the enemy host with his cannon and laser lance, his fury carrying him forward where Verticorda lived by his preternatural skill. The other Knights that still lived were the best of the order, the most sublime warriors he had fought alongside: Yelsic, Agamon and Old Stator.

Ahead, Verticorda saw the black pavilion where the architect of this confrontation watched the honourable Knights of Taranis dying for his amusement. The standard of Melgator, a golden chain upon a crimson field, flew above the pavilion and though a host of warriors and black machines stood between them, Verticorda vowed he would not be brought low while such an ignoble individual still lived.

More gunfire hammered the Knights, and Agamon was undone, the final strength of his shields torn away by the heedless sacrifice of scores of suicidal warriors rushing close and detonating explosive petards against his armour.