Now they would plan how to fight it.

The briefing chamber felt uncomfortably warm to Vauban, but he ignored the sweat prickling on his brow and made his way to his chair at the head of the meeting table. Regimental colours and plaques of all the regiments that had garrisoned this citadel over the centuries lined the walls and Vauban nodded respectfully to the ghosts of his predecessors.

Every seat was taken. The senior commanders from his battalions and heads of station were gathered around the long, oval table. The commanders of his regiment sat along one side: Mikhail Leonid, his second-in-command, and the three battalion commanders Piet Anders, Gunnar Tedeski and Morgan Kristan. Along the other side of the table sat the representatives of the Adeptus Mechanicus. Adept Naicin sat with his gloved hands laced before him, smoking a long cigar, his artificial lungs purging the smoke from exhaust ports along his flexing, silver spine. A retinue of blind scriveners and auto-recorders stood behind him, meticulously noting down their master's every movement and utterance.

Beside Adept Naicin, a brass-rimmed, holo-slate displayed a flickering image of an ashen face, haloed by wires and gurgling tubing. The face twitched as half-remembered muscle memories flickered across its features, their organic nature now subservient to the pulse of the machines around them. Arch Magos Caer Amaethon, Master of the Citadel of Hydra Cordatus, frowned from the depths of his machine-temple where he was forever linked to the beating, mechanical heart of the citadel, interfaced with every facet of its operation. So immersed in the internal matrix of the citadel, the scant remnants of Amaethon's body could never leave his mechanised womb buried deep in the heart of the fortress.

Junior officers circled the table pouring caffeine and handing out briefing notes packed with columns of numbers listing operational strengths of units and supply readiness.

Vauban grunted with distaste. 'There's three kinds of lies' he said, quickly scanning the document, 'lies, damn lies and statistics!'

Behind the table, tonsured technicians prepared the view-slate for the graphics Vauban had ordered and a gunmetal grey lectern was set up slightly to the side.

As the last of the techs and aides left the room, Vauban rose from his seat and moved to stand behind the lectern. The brusque commander exhaled a prodigious cloud of smoke and addressed the council of war.

'Well, gentlemen, we've been hit badly and the situation's probably only going to get worse before it gets better.'

A few scowls crossed the faces of his junior officers at this apparently defeatist statement. Vauban ignored them and continued.

'We don't have a lot of time, so I want to keep this as brief as possible. Then we can start getting even. We've taken a hit, and a damn bad one at that, but if we act now, I think we've got a good chance of kicking the enemy right in the teeth.

'First, I'm going to give you all a rundown on what we've been seeing from here. Now, I'll be fast, so keep up, and if I ask a question you'd better answer me quickly. But if you want to ask any questions, wait until I'm done.'

Taking the officers' silence as assent, Vauban turned to a large scale map of the citadel and its surrounding environs that had appeared on the slate behind him. Jericho Falls was highlighted in red, while the citadel, Tor Christo and the underground tunnel between the two were picked out in green.

'As you can see, the enemy have taken Jericho Falls and has denied us any hope of utilising the facilities there. This also precludes us from expecting any air cover or superiority.'

Vauban turned to face Gunnar Tedeski. 'How many aircraft were based there, Major Tedeski?'

The stocky major was a small man, an ex-Marauder pilot with one arm and a crudely cauterised right eye socket of burnt flesh. Shot down whilst strafing an ork convoy, he had been taken prisoner and tortured by the greenskins before being rescued by warriors from the Ultramarines Fourth company.

Tedeski answered without consulting his notes. 'Five squadrons of Lightnings and four of Marauders. A total of one hundred and twelve aircraft, mostly air interceptors and, we suspect, mostly destroyed.'

'Very well, so at least we can be fairly sure that the enemy won't be using our own craft against us. Anyway, putting that to one side for now, we still have the logistical and strategic advantage. How long that con—'

'Excuse me, Colonel Vauban,' interrupted Magos Naicin, 'but can you explain how you arrived at such a conclusion? It is my understanding that we have lost the one lifeline we had to the outside world and now the enemy is using our own facilities to land yet more troops and war machines. I fail to see how this is to our advantage.'

Vauban didn't bother to hide his annoyance, leaning on the lectern and speaking as though to a particularly stupid junior officer.

'Magos Naicin, you are a man of science, not war, so you cannot be expected to understand, but it is plain to me that this attack on our citadel cannot succeed. We have over 20,000 soldiers, a brigade of armoured vehicles and a demi-legion of the Legio Ignatum at our disposal. I know this fortress and have read the journals of its former castellans. The kill ratio for the citadel's bastions is, at worst, four to one and I am sure that even you will admit that such numbers are beyond the pale of what we can expect from any opposition.'

Naicin bristled at such a dismissive answer, and Vauban returned to the view-slate. Troop dispositions flashed up onto the screen, and Vauban pointed to each glowing icon in turn. 'Our forces are dispersed throughout the main commands. Battalion C is based here along with Battalion B, altogether some 12,000 soldiers and 900 armoured vehicles. Battalion A was split between Jericho Falls and Tor Christo, and, taking into account the losses suffered at Jericho Falls, the battalion now stands at a little under 7,000 men, all currently based in Tor Christo.'

The viewscreen changed again as enemy troop positions and strengths were overlaid on the map.

'As to the enemy, we know that since the battle at the Falls, very little has moved out of the spaceport. As to their numbers we can only guess, but we're assuming they can't have more than 30 to 40,000 soldiers, well armed and, right now, well motivated and led.'

Vauban paused to let the hugeness of the number sink in, pleased to note the absence of any fear in his audience.

'Right then, so that's the situation, as far as we can understand it. Now I want each of you to give the rest of us a quick update on your commands. Nothing fancy, and be honest. If your unit's a mess, short of supplies or otherwise below par then I need to know about it. Understood?'

Vauban addressed the flickering, holographic figure of Magos Amaethon at the end of the table. 'Arch Magos Amaethon, you are closer to the workings of this fort than most men, is there anything I need to know?'

The image of the arch magos fluttered on the holo and Vauban was about to repeat his question when Amaethon answered, his voice wavering and unsure.

'I believe we must hit hard and hit quickly… yes. This citadel is strong… but any fortress will ultimately fall unless it is assured of relief, you see. We are on borrowed time unless we know that reinforcements are on their way to us. We must strive to hold out until reinforcements can arrive.'

'Very well, you all heard the magos. I want full ammo inventories by tomorrow morning from every station. Now normally I don't like reacting to an enemy's moves, it gives him the initiative and keeps us on our back foot. However, in this instance, I don't think we've got much choice.'

Vauban turned to his battalion commanders. 'Gunnar, Piet, Morgan? What's the status of your units?'