'It has not failed him before,' pointed out Obax Zakayo.

'He hasn't fought me before,' said Honsou.

The trenches ahead were lit by drumfires, and the clang of digging shovels and the rumble of earth-moving machines was all but obscured by the thunder of guns.

'Onyx,' whispered Honsou, unsheathing his black bladed axe. 'Go.'

Onyx nodded, a fluid shadow and all but invisible in the darkness, slithering on his belly towards the trenchline, his outline blurring and merging with the night. Obax Zakayo said, 'If he is discovered, we will all die here.'

'Then we die,' snarled Honsou. 'Now be silent or I will kill you myself.'

Suitably chastened, Obax Zakayo said nothing more as he heard the sound of gurgling cries and slashing blades from ahead. Honsou saw a fountain of blood spurt above the line of the trench and knew that it was now safe to approach.

He crawled to where Onyx had cut a path through the razorwire and dropped into the trench. A score of corpses filled the trench and adjacent dugout, blood, glistening and oily in the firelight, coating the walls and seeping between the well laid duckboards. Each body lay sprawled at an unnatural angle, as though every bone had been broken. Each bore a long gash up the centre of their backs where their spinal column had been ripped out. Onyx himself stood immobile in the centre of the trench, slowly sheathing bronze claws into the grey flesh of his hands as the silver fire of his veins burned even brighter than normal. The daemon within him revelled in the slaughter and allowed the human part of him to return to the surface once more.

'Good kills,' said Honsou as his Iron Warriors dropped into the trench, spreading out and securing their entry point. He ran over to the communications trench at the back of this widened area and ducked his head around the corner. Just as he had expected, he could only see partway along it, the trench following a standard zigzagging course. Further down its length, he could see red-liveried soldiers and slaves.

'Have you no imagination, Berossus?' he chuckled to himself. 'You make this too easy.'

He turned away and gathered his warriors about him. 'It is time. Let's go, and remember, as far as anyone here knows, we are loyal Iron Warriors of Berossus. Let no one challenge that.'

His warriors nodded and, with Honsou in the lead, they set off down the communication trench. They walked with the confident, easy swagger of warriors who know they are without equal, and all the human and mutant labourers of Berossus abased themselves before them as they passed.

They passed dugouts filled with twisted mutant creatures gathered in chanting groups around shrines to the Dark Gods, their mutterings overseen by sorcerers in golden robes. None questioned them, none had any reason to, honoured to have ancient warriors of Chaos pass by. Honsou saw bright arc lights suspended on baroque towers of iron that reared into the night and were hung with all manner of bloody trophies. Chanting groups of robed figures surrounded them, Honsou stopped and asked, 'Zakayo, what are these towers? This doesn't look like something Berossus would do.'

'I am not sure,' replied Obax Zakayo. 'I have never seen their like.'

'They seek to break the walls of Khalan-Ghol with sorcery,' said Onyx. 'The towers are saturated with mystical energy. I can feel it, and the daemon within me bathes in it.'

'What?' hissed Honsou, suddenly wary. 'Are their magicks strong enough to overcome the kabal and the Heart of Blood?'

'No,' said Onyx. 'Not even close. There is great power here, but the Heart of Blood has endured for an eternity and no power wielded by a mortal can defeat it.'

Honsou nodded, reassured that the mystical defences of his fortress would hold. He glanced at the towers.

'This smells of Toramino,' he said. 'Berossus would not have thought of it.'

'Aye,' agreed Obax Zakayo. 'Lord Toramino has great cunning.'

'That he does, but I'll see that arrogant bastard dead before he takes Khalan-Ghol, sorcery or not.'

Passing beyond the towers, Honsou and his warriors emerged from the trench lines without incident, watching as the sweating, straining army of Berossus sought to bring his fortress to ruin. Tracked dozers laden with shells rumbled past behind high earthworks and Honsou was forced to admire the thorough completeness of the siegeworks. Forrix himself would have been proud.

Plumes of fire shot up from an iron refinery. The thunder of processing plants producing explosives and the hammering of forges filled the plains: millions of men working to bring him down. Stockpiles of ammunition and brass-cased shells were stored in armoured magazines and as they passed each one, Obax Zakayo would enter and place an explosive charge from the dispenser on his back. Honsou knew that Obax Zakayo was, in all likelihood, a liability, too entrenched in the old ways of his former master to be part of Honsou's cadre of lieutenants, but no one knew demolitions and explosives like he did.

And he had a cruelty to him that appealed to Honsou's sense for mayhem.

The further back they travelled from the front trenches, the greater the risk of discovery became. He saw sturdily constructed barrack-bunkers and great artillery pits that had obviously been built by Iron Warriors, and heard roaring bellows of madness that could only mean the cage-pits of the dreadnoughts were near.

'It is folly to continue, my lord, we should retreat now,' said Obax Zakayo. 'We have placed enough explosives to disrupt Berossus for months.'

'No, not yet,' said Honsou, a reckless sense of abandon driving him onwards as he caught sight of a familiar banner flapping in the wind atop an armoured pavilion. It squatted in the shadow of one of the colossal Titans, beyond a forest of razorwire and a staggered series of bunkers. 'Not when we have a chance to deliver something a little more personal to Lord Berossus himself.'

Obax Zakayo saw the banner and said, 'Great gods of Chaos, you cannot be serious!'

'You know I am, Zakayo,' said Honsou. 'I never joke about killing.'

Dug seven metres down into the rock, the sides of the artillery pit were reinforced with steel-laced rockcrete, at least two mettes thick. Angled parapets, designed to deflect enemy artillery strikes swept up over the embrasure the huge siege gun would fire through. Honsou knew that none of his artillery pieces could reach this far and that such endeavour was wasted effort, but it was so like Berossus to have them built anyway.

The mighty cannon's bronze barrel was silhouetted against the roiling clouds above, etched with great spells of ruin and hung with thick, drooling chains of desecrated iron. It sat at the base of an incline on rails, so that after each shot it would roll back into its firing position.

Perhaps a hundred human soldiers surrounded the huge cannon, guards to protect the mighty siege gun. Honsou and his warriors brazenly marched towards the artillery pit, daring the soldiers to stop them. Though he and his warriors proudly displayed the heraldry of the Iron Warriors, it would not take the soldiers long to realise that they did not belong here and raise the alarm.

Honsou could see they were attracting stares, but pressed on, pushing the bluff to the limit as an Iron Warrior with a heavily augmented head and arms climbed from the artillery pit. Red lights winked on his helmet, fitted with range-finders, trajectorum and cogitators, and Honsou knew he looked upon one of Berossus's Chirumeks. More machine to him than man, the practitioner of the black arts of technology scanned him up and down before a huge gun affixed to his back swung around on a hissing armature and aimed at them.

Onyx never gave him a chance to fire the weapon, leaping forward with the speed of a striking snake. His outline blurred, becoming oily and indistinct as he moved. A flash of bronze claws and a rip of flesh and the Chirumek collapsed, his spinal column held aloft by the daemonic symbiote.