The traitors had made their way to within metres of the trench. Directly opposite him, a giant in armour stained the violent turquoise of ocean-corroded iron turned his weapon upon Varens. He thought then he would surely die. Then the emplacements at either end of their section opened up, raking the traitors with fire. He watched in amazement as the Plague Marine’s obese frame absorbed four heavy bolt-rounds, the explosions of their detonations in his massive body sending squirts of ichor out of the holes in his armour. The traitor shook, but did not fall. He only succumbed to the impact of the fifth, and keeled over like a rotten tree into the quagmire.

A new wave of flies battered against Varens’ helmet, hard as death-world hail, obscuring his vision with swirling curtains of pale, furry bodies. Then they were gone once more, and the traitors were at the trench.

Three Heretic Astartes attacked Varens’ section, tossing wizened heads before them that exploded like grenades. A choking gas filled the trench, and several men fell to the poisons within as the smoke ate through their respirators.

‘All is ash, all is ash,’ the traitors sang.

The Plague Marine nearest Varens stepped onto the edge of the earthwork. Dozens of lasbeams found him. His corroded armour turned the light aside, or else the beams were absorbed by his monstrously bloated body. Pulsing, rotting organs hung through gaps in the ancient ceramite. Oil dribbled from the armour’s ailing systems, and the reactor unit on his back hitched and coughed with the maladies of machines.

The wooden and plasteel facing of the trench gave way under the traitor’s immense weight, and he rode the collapsing wall down, bringing a wave of sloppy mud and broken flesh with him.

He rose over Varens. Half his helmet had corroded away, exposing rotten teeth and a single yellowed eye. The remains of the helm looked like it had melted somehow into the warrior’s flesh, becoming one with it, but incompletely so – the bottom still moved as a separate artefact, whereas at the top, rippled, green skin melded with the metal into a semi-living mass dotted with suppurating boils. A grey horn sprouted sideways from the warrior’s temple, the cracked mess at its root bleeding yellow plasma.

Behind the giant, others of its kind fought with stolid efficiency, bludgeoning their way through the dozens of mortals who opposed them. There was shouting, and much weapons fire, and the crack of disruption fields as auxilia officers brought their power weapons to bear, but Varens saw only a little of it past the steaming, diseased bulk of the Plague Marine bearing down upon him.