Too loud, too close to be just the wind, thought Bostok. He took up his lasgun as he turned to face the dark.

Silhouettes lived there, jerking in stop-motion with every void impact flare – they were his comrades, those who had made it to the five hundred metre line.

Bostok’s eyes narrowed.

There was something else out there too. Not guns or Phalanx, not even rebels.

It was white, rippling and flowing on an unseen breeze. The rain was so dense it just flattened; the air didn’t zephyr, there were no eddies skirling across the killing ground.

‘Sarge, do we ’ave Ecclesiarchy in our ranks?’

‘Negative, trooper, just the Emperor’s own: boots, bayonets and blood.’

Bostok pointed towards the flicker of white.

‘Then who the frag is that?’

But the flicker had already gone. Though the bells tolled on. Louder and louder.

Fifty metres away, men were screaming. And running.

Bostok saw their faces through his gun sight, saw the horror written there. Then they were gone. He scanned the area, using his scope like a magnocular, but couldn’t find them. At first Bostok thought they’d fallen foul of an earth ditch, like the heavy bolter and infantry he’d seen earlier, but he could see no ditches, no trench or fire pit that could’ve swallowed them. But they’d been claimed all right, claimed by whatever moved amongst them.

More screaming; merging with the bells into a disturbing clamour.

It put the wind up Sergeant Harver – Phalanx soldiers were disappearing in all directions.

‘Bostok, Genk, get that cannon turned about,’ he ordered, slipping out his service pistol.

The lascannon was well and truly stuck, but worked on a pintle mount, so could be swivelled into position. Genk darted around the carriage, not sure what was happening but falling back on orders to anchor himself and stave off rising terror. He yanked out the holding pin with more force than was necessary and swung the gun around towards the white flickers and the screaming, just as his sergeant requested.

‘Covering fire, Mr Rhoper,’ added Harver, and the vox-operator slung the boxy comms unit on his back and drew his lasgun, crouching in a shooting position just behind the lascannon.

Bostok took up his post by the firing shield, slamming a fresh power cell into the heavy weapon’s breech.

‘Lit and clear!’

‘At your discretion, trooper,’ said Harver.

Genk didn’t need a written invitation. He sighted down the barrel and the targeting nub, seeing a flicker, and hauled back the triggers.

Red beams, hot and angry, ripped up the night. Genk laid suppressing fire in a forward arc that smacked of fear and desperation. He was sweating by the end of his salvo, and not from the heat discharge.

The bells were tolling still, though it was impossible to place their origin. The void-shrouded city was too far away, a black smudge on an already dark canvas, and the resonant din sounded close and all around them.

Cordite wafted on the breeze; cordite and screaming.