‘Hell Night, in more than just name it seems,’ said Ba’ken, looking up to the bloody heavens.

‘An inauspicious omen, perhaps?’ offered Iagon, the first time he’d spoken since landfall.

‘Ever the doomsayer,’ remarked Ba’ken under his breath to his sergeant.

But Dak’ir wasn’t listening. He was looking at Pyriel.

‘Form combat squads,’ said the Librarian, when he realised he was under scrutiny. ‘Tsu’gan, find positions.’

Tsu’gan slammed a fist against his plastron, and cast a last snide glance at Dak’ir before he divided up his squad and moved out at a steady run.

Dak’ir ignored him, still intent on Pyriel.

‘Do you sense something, Brother-Librarian?’

Pyriel eyed the darkness in the middle distance, the no-man’s land between the bastion and the shimmering edge of the far off void shield. It was as if he was trying to catch a glimpse of something just beyond his reach, at the edge of natural sight.

‘It’s nothing.’

Dak’ir nodded slowly and mustered out. But he’d detected the lie in the Librarian’s words and wondered what it meant.

False thunder wracked the sky from the report of heavy cannons at the rear of the Imperial battle line. Smoke hung over the muddied field like a shroud, occluding the bodies of the Phalanx troopers moving through it, but was quickly weighed down by the incessant rain.

They marched in platoons, captains and sergeants hollering orders over the defensive fire of rebel guns and the dense thuds of explosions. Heavy weapons teams, two men dragging unlimbered cannons whilst standard infantry ran alongside, forged towards emplacements dug five hundred metres from the shield wall.

Incandescent flashes rippled across the void shield with the dense shell impacts of the distant Earthshaker cannons and from lascannon and missile salvoes, unleashed when their crews had closed to the assault line.

In the midst of it all were the Salamanders, crouched down in cover, at the edges of the line in five-man combat squads.

Librarian Pyriel had joined Dak’ir’s unit, making it six. With the flare of explosions and the red sky overhead, his blue armour was turned a lurid purple. It denoted his rank as Librarian, as did the arcane paraphernalia about his person.

‘Our objective is close, brothers. There…’ Pyriel indicated the bulk of a generatorium structure some thousand metres distant. Only Space Marines, with their occulobe implants, had the enhanced visual faculty to see and identify it. Rebel forces, hunkered down in pillboxes, behind trenches and fortified emplacements, guarded it. In the darkness and the rain, even with the superhuman senses of the Astartes, they were just shadows and muzzle flashes.

‘We should take an oblique route, around the east and west hemispheres of the shield,’ Dak’ir began. ‘Resistance will be weakest there. We’ll be better able to exploit it.’

After Tsu’gan had secured the route, the Salamanders had arrived at the five hundred metre assault line, having stealthed their way to it undetected before the full Imperial bombardment had begun. But they were positioned at the extreme edges of the line – two groups east, two groups west – in the hope of launching a shock assault into the heart of the rebel defenders and destroying the generatoria powering the void shield before serious opposition could be raised.