ARCATUS EYED THE channel ahead with suspicion. The passageway was long and narrow, no more than two metres wide and at least three hundred metres long, turning abruptly to the right to continue out of sight. About fifty metres away, a small gutter-like trench emerged from the wall, cutting diagonally across their line of advance. He called his Custodians to a halt and waited for instruction from Corax. In the three and a half hours since he had entered the Labyrinth, Arcatus had found a new respect for the primarch, and perhaps even a little trust. Four times, Corax’s last-minute warnings or orders had saved the him and his group of Custodians and Raven Guard from deadly traps and mechanical attack. Only a few minutes earlier, Arcatus had drawn back just in time to avoid a vaporous acid spray that would have melted through his armour in seconds.
A rivulet of liquid ran along the channel, a dark green, viscous fluid that flowed sluggishly, its level growing higher.
‘I think this passage is going to be flooded, Corax,’ Arcatus reported.
‘It is just lubricating fluid,’ the primarch replied. ‘It is no threat. Proceed to the end of the passageway. There will be three doors. Take the door on the left. Beyond is some kind of energy grid, a laser trap perhaps. Be wary.’
This last comment seemed unnecessary – Arcatus had been wary from the moment he had first stepped into the deadly maze. He followed Corax’s instructions, taking the squad to the bend in the corridor. A shouted warning caused him to turn as a previously invisible hatch opened in the ceiling. Three silver orbs, each no bigger than his fist, dropped into view.
The first exploded into molten shards as Custodian Ganius swept the blade of his guardian spear through it. The other two detonated of their own accord, showering Ganius and the Raven Guard next to him with jagged, smoking shrapnel. Wisps of vapour rose from their armour as the acidic compound melted swiftly through to flesh.
Ganius cried out – the first time Arcatus had ever heard a Custodian react to pain – and struggled to disconnect his breastplate. The Raven Guard legionary toppled to the floor with a crash, a hole melted through his helm, a slush of liquefied skull and brain matter dribbling onto the bare floor.
‘It’s through my ribs!’ snarled Ganius, dropping to one knee, clutching at his chest.
Arcatus acted without thought, to spare Ganius the inevitable agony of having his heart and lungs melted. His power halberd gleamed with energy as he swung the weapon, taking Ganius’s head from his neck in one stroke. Ganius’s decapitated corpse flopped to the ground, the echo of the impact resounding along the passageway.
‘Move up, door on the left,’ Arcatus snapped, waving his halberd to get the survivors advancing.
He stood over the remains of Ganius, alert for any more of the silver globes. Arcatus followed after the last of the Raven Guard to pass, remembering the primarch’s promise that the vault contained something that would ensure Horus’s defeat. With a last glance back to Ganius’s body, which was collapsing in on itself as the acid chewed through his spine, Arcatus vowed to himself that he would hold Corax to his word.
NINE
The Depths of Terra
Nikaea’s Legacy
Genesis of the Primarchs
THE GENE-TECH VAULT lay within reach. Corax allowed himself a moment to see if he remembered anything about the inner defences, but there was nothing in the Emperor’s memories. Once through the Labyrinth, Corax would simply have to unlock the vault doors and they would stand before the prize.
‘Ready your servitors,’ the primarch told Nexin. ‘We enter the Labyrinth in two minutes.’
Twenty-three Raven Guard were dead, another seventeen crippled and left in the Labyrinth to be recovered later, a further thirteen wounded but able to continue. The Custodians had also lost three warriors. Corax had committed all of their names to memory but now was not the time to mourn or mark their passing. The Labyrinth remained to be unlocked.
Corax’s commands continued to spill from his lips in a constant stream, moving the pieces of the puzzle to where they were needed. He tried not to think of them as living, breathing warriors. Ever since he had first sent his prison-army to fight against the guards of Lycaeus, he had known his orders would see men die. Though the adversary he now attempted to outwit was no sentient foe – though, in a sense, he was being pitted against the guile of the Emperor himself – the sacrifices required were no different. Millions, probably billions, of the Emperor’s followers would die if the Raven Guard failed today and could not cause Horus to pause in his advance on Terra.
So it was that the chatter of bolter fire that now echoed distantly from the maze and blared harsh over the vox-net did not divert his attention from the task. He thought only of report and command. His Legiones Astartes had sworn oaths to lay down their lives in his service and for the cause of the Emperor, and it would be vanity to think this battle was any different.
The lead elements of the force were almost two-thirds of the way through the maze. Parts of the Labyrinth had been secured – the positions of the squads and the routes they had taken forcing the mechanism of the Labyrinth into impossible choices so that engines broke, pistons froze and gears seized.
The hardest part was over. The remaining possible configurations had dwindled to the extent that Corax could clearly see the path ahead. It was just a matter of time until the Labyrinth was bested. The primarch warned himself against complacency. The Labyrinth was still a random device, constantly changing, and could throw up a challenge he had not yet encountered and could not foresee. His brave Raven Guard and the warriors of the Legio Custodes still placed their lives in his hands.
He directed several squads to converge on a massive turntable that would open up a main accessway towards the inner reaches of the mountain. This done, he signalled Arcatus on a direct channel.
‘Custodian, you must move your men into the chamber flanking your right,’ he said. ‘You will be breaching a line of strong defences. Be prepared.’
‘The Custodian Guard is always prepared, primarch,’ Arcatus replied. ‘It seems from the reports I have been hearing that you have directed my squad into the teeth of the hardest opposition. Perhaps you hope we will fall, and thus rid yourself of our scrutiny?’
‘I have no desire to do so,’ Corax replied without rancour at the accusation. ‘Had I wished you disposed of, I have had many opportunities already. Your warriors see the hardest fighting because they are the best under my command. You and your men have abilities even above those of my legionaries and so it is against the toughest challenges you have been pitched. The Raven Guard owes you a debt of honour for your aid, which I have found of the highest value, making this task a little easier for all of us.’
There was no reply for a while, the Custodian perhaps taken aback by Corax’s words.
‘Very well,’ Arcatus said. ‘We shall continue as you say.’
The whine of hydraulics caught Corax’s attention as Nexin and his servitors joined the primarch.
‘The vault is open?’ the magos asked.
‘It will be soon,’ said Corax. He worked out the quickest route through the Labyrinth to the front of the advance and pointed to one of the openings. ‘This way. Follow me.’
STANDING CLOSE TO Corax, Alpharius could hear the primarch’s conversation with Arcatus, Agapito and the tech-priest. They discussed the immense vault door that now barred further progress. It was circular, five metres across, and of a metal that reflected the light dully, something which Alpharius had not seen before. The hinges were massive, as tall as him, but there was no sign of a locking mechanism: no runepad, no scanner, not even a keyhole. Around the door smoked the remains of four gun turrets that had sprung from the floor as the lead elements of the force had approached.
Alpharius listened patiently as the commanders discussed the options. Agapito favoured melta charges, but the primarch was not convinced they would breach the barrier. The magos claimed his servitors could cut their way through.