‘A wise move,’ Ainoc said mockingly. ‘Not all species are as sure-footed as the eldar.’
They descended carefully all the same, eldar in front, Space Marines behind, the Techmarine in the rear. Brother Gad read out the depth in ever-increasing numbers. They were four kilometres down, now, and it was as hot as a steam-bath, the atmosphere inimical to all but the most tenacious of life-forms.
The spool ran out, and Heinos slammed in the last piton, setting down a small, sputtering long-life flare beside it. Fifty metres along from that, and the lava-tube turned sharply to the right, and then branched out.
The even, slippery basalt gave way to cliffs of white crystalline pillars, hexagonal, some as perfectly geometric as if carved out by precise instruments. They reared up on all sides, and the air shifted somewhat, became lighter. Fornix looked up to see the roof of the cavern some hundred metres above his head, more crystals hanging down from it in stalactites as numerous as the pipes of some great organ, all colours of the rainbow catching the light in an arced prism, curtains of crystal sweeping back and forth. It was as though an ancient sea had been frozen in mid-surge, and then emplaced in the cavern ceiling. Some of the eldar exclaimed aloud at the beauty of the sight.
‘This is no geological oddity,’ Ainoc said, wonder in his voice. ‘Our people did this, in years ago uncounted. This is a prayer-space, made for contemplation and enlightenment.’
The Space Marines stood in standard combat formation, sweeping the shadows with the muzzles of their bolters.
‘High levels of chlorine and hydrogen in the atmosphere,’ Brother Gad said. ‘Water vapour in small quantities. It’s coming from up ahead.’
‘This is a holy place of our people,’ Ainoc said to Fornix. ‘It might be better if you and yours were to remain here for now.’
‘I think not,’ Fornix told him. ‘I have orders, xeno. One of them was to keep you in my sight at all times.’
Ainoc shrugged as if it were not important, but there was anger thickening in his voice. ‘Very well, human. But tread softly in this place. You are not welcome here.’
‘I can’t remember the last time I was welcome anywhere,’ Fornix retorted. ‘You can pray in your own time – now let us get on with the task in hand.’
Ainoc hissed something venomous in his own tongue, then barked a command, and the eldar stopped staring around them and followed him in a staggered file.
The Space Marines brought up the rear, the cameleoline upon their armour catching the radiance of the crystalline formations around them, so that they seemed to be bright, iridescent giants of sparkling light.
Camouflage has its limits, Fornix thought.
They heard a new sound: water flowing in rivulets. It crossed their path, a river of it, flashing and dancing in the light. But steam rose from it, and when Brother Gad swept it with the auspex he stepped back a pace.
‘Hydrochloric acid, highly concentrated. If we walk through it, we’ll lose our legs.’
‘Elegant,’ Ainoc said. ‘I believe all this has remained untouched since the Eye of Terror was born. I cannot believe I stand in such an ancient planet-bound construction of my race.’
‘Try elegantly walking across it,’ Fornix said dryly.
‘I’m sure you and your mechanical monstrosity have some kind of idea,’ Ainoc quipped, and stood aside.
Brother Heinos joined them. Fornix set a hand on his arm. In some ways, Heinos was more unknowable to him than any Space Marine he had ever encountered. Even Jord Malchai was a brother. But Heinos had been thirty years on Mars, praying to other gods, and learning rituals no ordinary Space Marine could ever penetrate.
But he was a Dark Hunter, and that was enough.
‘Brother, I think we need some inspiration,’ Fornix said.
Heinos stopped and stared at the twenty-metre width of the acid river. His hand came up and touched the Machina Opus badge which was inlaid on one pauldron. Then he looked at the roof of the crystalline cavern above.
‘All our brethren have coils of high-tensile cable on their belts. I could fire a piton above, and we could swing across.’
Fornix thought it over.
‘Perhaps there is a simpler way.’ He strode over to a crystal pillar, the cameleoline on his armour catching its light, and with his power fist he grasped it near the base. The energy-charged fingers sank into the crystal, sizzling.
‘What are you doing?’ Ainoc cried.
With a grunt, Fornix broke the pillar free of its base and it toppled over with a crash. He stood a moment, while the eldar exclaimed in dismay and anger. Ignoring them, he shoved the hexagonal crystal, half a metre wide and thirty metres tall, across the floor of the cavern, and rolled it to the bank of the acid river.
‘Push it out. Steyr, Pendar, lend a hand here.’
The crystal was shoved out by the other Dark Hunters. Halfway across, the tip of it sank beneath the acid. But the river was not deep.
‘Two or three more should do it. Brother Heinos, lend me your arm.’
The eldar had gone silent. They watched as the Adeptus Astartes helped their first sergeant fell several more of the crystalline columns and drag them to the edge of the stream. These were pushed out over the first. It took four to finally bridge the deadly river of hissing liquid, and the acid foamed white upon the crystal bridge, releasing clouds of gas as it ate into it.
‘Shall we?’ Fornix asked Ainoc, panting.
‘That was wanton sacrilege, and I will not forget it,’ the eldar warlock said.
‘Xeno, I don’t care what you call it, but I had no wish to go swimming today. Now let us move on, while we’re still young.’
The warlock stood stock-still. His loathing of the Space Marines before him was almost palpable. But he lurched into motion at last, and led his people swiftly over the makeshift bridge. They barely seemed to set foot upon it before they were over the river.
The Space Marines followed more slowly. Fornix saw the red sigils blink on and off in his helm as spurts and splashes of acid jumped up to lick at his armour, but the damage was minimal. Before him Brother Gad, gaze fixed on the auspex, slipped and nearly fell, but Fornix caught him with his free hand.
‘Keep an eye for your feet, you young fool.’
Once the entire company was on the other side, Ainoc spoke again.
‘The Circuit will not have been left unguarded. We must proceed with great care now. I sense it up ahead, but there is something else which exists nearby, like a shadow of memory.’
‘A shadow,’ Fornix said. ‘Well, let us see if we can shed some light upon it. Lead on, xeno.’
The company started out again, eldar in front, Space Marines behind, meandering in a double file through tall pillars of crystal like pilgrims traversing the nave of a great cathedral. And the dust they kicked up floated in the air around them, alive and sparkling with iridescent light.
As they progressed, so the light grew around them, and the structures became more regulated, until even the Space Marines could dimly grasp a sense of the overall design. And now there were other elements as well. The pale arching vaults that rose above them were now upheld by sinuous beams of wraithbone, some smooth and rounded, others as sharply planed as the blade of a knife.
They traversed this space for over an hour, while every so often Brother Gad called out the distance and bearing with monotonous regularity.
Fornix called ahead to the tall eldar warlock at the front.
‘This thing you search for – if it is so precious to your people, then how did it end up buried at the core of an Imperial world?’
Ainoc’s stride did not slow.
‘This world was ours once, mon-keigh. It was named Vol-Aimoi, and before the Eye of Terror opened, this planet, and the entire system, were located somewhere else. But the cataclysm of Slaanesh’s birth shunted it through space, stripping it of its beauty and its people.