He only hoped that the sculptures shattered below them had not contained the information he needed.
'Gak me sideways!' someone shouted. 'Company!'
Thaddeus glanced upwards. There were lights now in the darkness at the top of the cylinder, powerful spotlights swinging through the shadows. The lights picked out ropes coiling downwards and figures rappelling down them, troopers in rust-red jumpsuits, guns slung on their backs.
'Frag, tech-guard!' said Kindarek.
Half the storm troopers were still pinned down by the servitors. Thaddeus didn't hold out much hope that those who remained could deal with crack tech-guard troops firing on them from above.
He spotted a couple of tech-priests directing the tech-guard, robed and hooded adepts armed with shimmering power axes and exotic weaponry that sent bolts of power burning down at the storm troopers.
The data-slate began to sort through the information according to the same codewords that Thaddeus had used to filter astropathic traffic - Soul Drinker, purple, Marine, spider, a host of others.
As the screen seethed with information Thaddeus switched to the vox frequency he had reserved for the shuttle.
Thaddeus to shuttle. Target above us, multiple hostiles. Make it count.'
'Received.’ came the servitor's mechanical voice, the signal warped by the intervening liquid hydrogen. 'Shuttle out.'
A fountain of hydrogen burst out of the lake and with a roar the shuttle's stealth engines kicked in, ripping it out of the lake and sending it hurtling upwards like a bullet from a gun. Once clear of the lake the main engines erupted and the shuttle rose on a plume of flame, past the lowest walkways and upwards.
The data now rushing through the uplink device still poured through the cogitator in awesome amounts. Every Mechanicus outpost from the present day back to the time of the Great Crusade was listed, with staff lists, schematics, work rotas, research reports, accounts, tech-prayers, and all the ephemera of the Mechanicus's immense operation.
Thaddeus keyed in the last command he had -the order to sort the data by the staff list Sister Aescarion had recovered from the outpost on Eumenix. A few hundred names that represented the last hope - maddeningly, everything Thaddeus needed to know was probably streaming past in front of his eyes, he just had to pick it out from the ocean of information.
The datastream thinned. A blinking green light on the frame of the data-slate told Thaddeus that the information was concise enough for the cogitator to hold. Thaddeus pressed a switch and the information was seared onto the cogitator's memory.
Maybe it was enough. Maybe there was nothing there but trivia. Thaddeus would have to take the chance, if he survived. That was a big if.
The shuttle soared upwards shattering its way through walkways as it went. Mounted guns on the half-glimpsed structures above pumped a stream of shells into the shuttle, ripping through the armour plates and sending sudden, shocking gouts of flame bursting from the engine housings.
The first tech-guard were landing on walkways high above, sending down hails of rapid-firing autogun shots. The freezing air was full of shrapnel and vapour. Thaddeus saw Sergeant Telleryev ripped clean in two by one of the last servitors, his insides turning to a mist of crimson shards even as two of his men were shot off the walkway by tech-guard fire. Thaddeus blasted twice, three times, and three tech-guard were picked off their rappel lines by ammunition they could only have dreamed of using one day.
The shuttle's engine blew and clouds of vapour bloomed around it. Its rise peaked and it began to fall, just a few metres beneath the levels the tech-guard were now landing on.
The servitor-pilot, working to hardwired protocols Thaddeus himself had installed, switched the shuttle's fuel cells into reverse, pumping high-grade prometheum derivative backwards until it flooded through the ignition chambers.
The fuel ignited and incinerated everything in the cockpit and crew compartment in an instant. The servitor-pilot was atomised, metal components melted to gas, flesh disappearing.
The hull of the shuttle failed under the stress of the explosive forces within. With a thunderclap and a flash of flame that turned the crystal cathedral a blazing orange, the shuttle exploded, and boiling flame filled the top half of the cylinder.
Vapour, like a falling sky, billowed downwards and washed over the storm troopers. Thaddeus was blinded, bright white turning dark.
The vox was a mess of static. For a few seconds he was alone, encased in cold and confusion, fumbling blind as he tried to stuff the data-slate into the pocket of his HE suit. The shadowy shape of a storm trooper stumbled by then fell out of view, slipping over the edge of the walkway as random autogun fire spattered down through the darkness.
Something huge was falling. The sound of shattering crystal cut through the din, a high fractured crash growing rapidly closer. Shards of crystal, like huge glass knives, plunged through the darkness and the air was full of filaments. Spikes of icy cold jabbed at Thaddeus as fragments of crystal punctured his suit and cold air jetted in before the fabric tightened around the tiny wounds.
The huge burning hulk of Thaddeus's transport ripped down from above, trailing ribbons of flame, carving through the dense vapour like a comet. It took half the walkways with it, countless strands of the crystal web snapping, information vaults shattering into a blizzard of fragments. Men were screaming as they fell. Thaddeus expected any second to be dragged down with them, or to have his HE suit sliced open and his muscles turned to slabs of frozen meat.
The transport impacted far below, and a fraction of a second later the top layer of liquid hydrogen ignited.
The containment fields, designed to divert the energy of any ignition away from the information vaults above, compressed the heat and Shockwave downwards and outwards. But the hydrogen kept burning as the transport plunged through it and then its plasma drive imploded. Without the containment fields, the whole lake would have burned and turned the cathedral into a column of flame, incinerating everything inside. Instead, the explosion was forced down into the root of the cylinder, where the ferrofibre walls met the rock of Pharos.
The walls of the cylinder fractured catastrophi-cally, great black fissures rippling up the walls. The air shrieked out into the hard vacuum beyond, sucking men and debris with it. Thaddeus grabbed the data-vault beside him as razor-sharp crystal shard whipped past. Storm troopers and tech-guard tumbled past, flailing hopelessly.
The hydrogen lake, designed to keep the information vaults stable, had instead led to the whole cathedral being destroyed. The Adeptus Mechani-cus, in their obsession with technical perfection, had missed the obvious danger. It had never occurred to them that anything hostile could survive the extreme cold and the servitor-warriors, or that anything could detonate the lake with such ferocity that the confinement fields could not cope. It was holy ground, and holy information was inviolable.
The upper echelons of the Mechanicus could not imagine that a desperate, lone inquisitor would invade the Omnissiah's sanctum and would bring with him all the random, chaotic factors that could destroy it.
The irony was momentarily lost on Thaddeus as the columns broke away from the ceiling and swung around him, churning up the broken crystal into a storm of razors. Thaddeus's section of walkway broke away and suddenly the cylinder was whirling around him. The fissures tore on upwards and suddenly the whole top half of the cylinder boomed open, the stresses in the structure building up until the whole cylinder split like a seed pod.
Thaddeus tried to control his movement but he couldn't. He kicked fruitlessly against nothing, and glimpsed surviving storm troopers and tech-guard doing the same. The fires from below went dark as the air rushed out and there was nothing but darkness now, the ruins of the cathedral below him and the blackness of space above. The tide of escaping air carried him upwards and out of the cylinder and, as he span out past the limits of Pharos's artificial gravity field, he saw the damage inflicted on the rest of the cathedral. The fires had burst up into the neighbouring cylinders and flames boiled around the base of the cathedral.