Though the men in the Christo had been under fire for over a week, the range was too great for the enemy guns to do more than chip away at the walls. However, the range was ideal for delivering ricochet fire, which had dismounted a great many of Tor Christo's wall-mounted guns. Tedeski had ordered the remaining guns to be pulled back into the fort, and though casualties had been light - fifty-two men dead so far - that would all change when the batteries of the second parallel were completed.

But Tedeski had a surprise in store for Tor Christo's attackers.

Guns situated at the base of the rocky promontory, kept in reserve thus far, would soon make their presence felt when the enemy moved their heavy artillery forward into those newly constructed batteries.

'It won't be long now, Poulsen,' mused Tedeski.

'What won't, sir?'

'The attack, Poulsen, the attack,' replied Tedeski, unable to mask his irritation. 'If we can't stop them from completing those batteries, they will bring up their big guns and lob high explosive shells right over our walls. Then they won't need to batter our walls down, they'll be able to walk right up to the main gate and come in, because there will be no one left alive to stop them.'

'But the guns below will stop them, surely?'

'Possibly,' allowed Tedeski, 'but we'll only be able to pull that trick once. And that's assuming they don't know about them already. Remember that reconnaissance party we fired on at the beginning of all this?'

'Yes, sir.'

'Well there's every chance our enemies know of the guns down there, and have planned accordingly.'

'Surely not, sir. If the enemy had discovered them, they would have attempted to shell them before now, would they not?'

Tedeski nodded thoughtfully, resting his elbow on the stonework of the parapet, its sharply angled construction allowing a soldier to fire at attackers almost directly below.

'There is that, Poulsen, and that's the only reason I haven't had the passages below ground blocked. I can't risk not having those guns firing when the time comes.'

Emboldened by his superior officer's cavalier attitude to the potential danger of snipers, Captain Poulsen stood at the edge of the parapet and watched the bustling activity on the plains.

'I never thought to see such a thing,' he whispered.

'What?'

Poulsen pointed towards the towering form of the Dies Irae, standing immobile where the death of the Imperator Bellum had crippled it. Its lower legs were blackened and still smoking where the meltdown of the Imperial Titan had scorched it. Vast swathes of scaffolding and buttresses had been erected around its legs as hundreds of men worked to try and repair the grievous damage done to it. The Titan's upper body had escaped the worst of the blast and each day its guns would fire upon the citadel, wreathing its walls in tremendous explosions, daring its enemy to come out and face it once more.

Tedeski nodded, 'Nor I. It was an honour to watch so brave a warrior fight such a diabolical monster. His brother Titans will avenge him though.'

'And who will avenge us?' pondered Poulsen.

Tedeski rounded on his aide-de-camp and snapped, 'We shall not need avenging, Captain Poulsen, and I will have words with any man who publicly voices such an opinion. Do you understand me?'

'Yes, sir,' replied Poulsen hurriedly. 'I only meant—'

'I know what you meant, Poulsen, but do not say these things aloud,' cautioned Tedeski, waving his arm at the soldiers who manned the parapet and the gunners who tended their artillery pieces.

What do you think is the single most important element of a fortress, Poulsen? Its walls? Its guns? Its position? No. It is the men who stand behind its walls and say to the enemy, "No, you shall not take this place". The fighting spirit of these men is all that keeps the enemy beyond these walls and only by standing together, with faith in the Emperor and an utter belief in our ability to hold, will we prevail. Regardless of the facts, the men need to believe that we believe the Christo can hold. Otherwise we are lost.'

Poulsen nodded thoughtfully before saying, 'Do you believe we can hold, sir?'

Tedeski returned his gaze to the plains below. 'Ultimately, no, we cannot hold. Tor Christo will fall, but we will hold it for as long as we can. When I decide that the day is lost, I will order the withdrawal along the tunnels and overload our reactor to blow this place apart before I allow these bastards to make use of the Christo.'

Honsou pushed aside an emaciated slave worker and followed Forrix along the twisting trench that led to the forward parallel. As the two Iron Warriors passed, slaves hurriedly dropped their shovels and picks and abased themselves before their masters. Neither Forrix nor Honsou paid the wretched creatures any heed, too intent on the looming shape of Tor Christo above them. Honsou felt the familiar anticipation as they stepped into the main parallel and he saw the thoroughness with which it had been constructed.

It had been dug to a depth of three metres, the wall nearest Tor Christo angled inwards to minimise the effect of airbursting shells. Propped dugouts were cut into the trench sides where slaves slept, ate and died. Too bone-weary to dispose of their dead in any other way, corpses were pushed to the side of the trench, the rotted remains filling the air with the stench of decay. Timber boards on iron sleepers were laid across the base of the trench and Honsou was impressed with the speed with which Forrix had driven the trench forward.

'The first battery will be here,' said Forrix, pointing to a portion of the trench Honsou estimated was some six hundred metres from the base of the mountain. He could see that work had already begun on widening the trench. Thick sheets of steel were piled at the entrance to the new battery, ready to be laid across the ground to enable the big guns to fire without their recoil burying them in the ground.

Honsou nodded, looking up towards Tor Christo, picturing the angle of fire this guns placed in this battery would have.

The most vulnerable point of any fortification was its salient angles, the projecting points of its bastions where the ground in front was not covered by direct fire from the parapet. Forrix had dug the main sap directly towards the central bastion, with this forward parallel constructed well within the range of the fort's guns, but protected by their depth and earthen ramparts.

Honsou could see that batteries were being dug to either side of the bastion's salient, angled inwards so that the guns placed there would fire perpendicular to the face of the bastion and break it open efficiently. Once the walls had been breached with direct firing guns, howitzers would send screaming shells into the gap to sweep it clear of enemy infantry before the main attack went in. Even so, it was sure to be a bloody enterprise.

There was a pleasing inevitability to the mechanics of a siege thought Honsou, as he watched dying slaves digging the gun battery. He had heard tales that in ages past there was a prescribed series of stages an attacker would be forced to go through before it was deemed that he had done enough to earn the surrender of a garrison. Once it had been decreed that both forces had done all that honour demanded, the defenders would surrender and be allowed to quit the fortress carrying their weapons with their colours raised high. Such a notion was clearly ludicrous, and Honsou could not imagine a time when he would accept an enemy's surrender.

Once the Iron Warriors began a siege, there was no way to stop it.

When the great Perturabo had still led his warriors in battle, he offered his foes one chance to surrender before he had even planted a single shovel in the ground. Should that offer be refused, there would be no others, and such a siege could end only one way: in blood and death.