He could taste that the air was thick with lethal bacterial filth and biological contaminants, though none were even close to virulent enough to trouble his incredible metabolism. With the golden light of his sword to illuminate the way, Horus negotiated a path around the gantry, listening out for any signs of his warriors. The occasional distant crack of gunfire or clang of metal told him that he wasn't completely alone, but the whereabouts of the battles was a mystery. The corrupted inner structure of the ship threw phantom echoes and faraway shouts all around him until he decided to ignore them and press on alone.

Horus passed through the armorium and into the star-ship's central spine, the deck warped and canted at an unnatural angle. Flickering glow-globes and sputtering power conduits sparked and lit the arched passageway with blue electrical fire. Broken doors clanged against their frames with the rocking motion of the ship, making a sound like funeral bells.

Ahead he could hear a low moaning and the shuffle of callused feet, the first sounds he could clearly identify. They came from beyond a wide hatchway, toothed blast doors juddering open and closed like the jaws of some monstrous beast. Crushed debris prevented the doors from closing completely, and Horus knew that whatever was making the noises stood between him and his ultimate destination.

Some trick of the diffuse, strobing light threw jittering shadows from the mouth of the hatchway, and flickering after-images danced on his retinas as though the light came from a pict projector running in slow motion.

As the hatchway rumbled closed once more, a clawed hand reached out and gripped the smeared metal. Long, dripping yellow talons sprouted from the hand, the flesh of the wasted arm maggot-ridden and leprous. Another hand pushed through and clamped onto the metal, wrenching open the blast doors with a strength that belied the frailness of the arms.

The sensation of fear was utterly alien to Horus, but when the horrifying source of the sounds was revealed, he was suddenly seized with the conviction that perhaps his captains had been right after all.

A shambling mob of rotten-fleshed famine victims appeared, their shuffling gaits carrying them forwards in a droning phalanx of corruption. A creeping sensation of hidden power pulsed from their hunger-wasted bodies and swollen bellies, and buzzing clouds of flies surrounded their cyclopean, horned heads. Sonorous doggerel spilled from bloated and split lips, though Horus could make no sense of the words. Green flesh hung from exposed bones, and although they moved with the leaden monotony of the dead things, Horus could see coiled strength in their limbs and a terrible hunger in each monster's cataracted eyeball.

The creatures were less than a dozen metres from him, but their images were blurred and wavering, as though tears misted his vision. He blinked rapidly to clear it, and saw their swords, rusted and dripped with contagion.

'Well you're a handsome bunch and no mistake,' said Horus, raising his sword and throwing himself forward.

His golden sword clove into the monsters like a fiery comet, each blow hacking down a dozen or more without effort. Spatters of diseased meat caked the walls, and the air was thick with the stench of faecal matter, as each monster exploded with rotten bangs of flesh at his every blow. Filthy claws tore at Horus, but his every limb was a weapon. His elbow smashed skulls from shoulders, his knees and feet shattered spines, and his sword struck his foes down as if they were the mindless automatons in the training cages.

Horus did not know what manner of creatures these were, but they had obviously never faced a being as mighty as a primarch. He pushed further up the centtal spine of the starship, hacking a path through hundreds of organ-draped beasts. Behind him lay the ruin of his passing, shredded meat that reeked of decay and pestilence. Before him lay scores more of the creatures, and the bridge of the Glory of Terra.

He lost track of time, the primal brutality of the fight capturing the entirety of his attention, his sword strikes mechanical and bludgeoning. Nothing could stand before him, and with each blow, the Warmaster drew closer to his goal. The corridor grew wider as he pushed through the heaving mass of Cyclopean monsters, the golden sheen of his sword and the flickering, uncertain lights of the corridor making it appear that his enemies were becoming less substantial.

His sword chopped through a distended belly, ripping it wide open in a gush of stinking fluids, but instead of bursting open, the meat of the creature simply vanished like greasy smoke in the wind. Horus took another step forwards, but instead of meeting his foes head on with brutal ferocity, the corridor was suddenly and inexplicably empty. He looked around, and where once there had been a host of diseased creatures bent on his death, now there were only the reeking remains of hacked up corpses.

Even they were dissolving like fat on a griddle, vanishing in hissing streamers of green smoke so dark it was almost black.

'Throne,' hissed Horus, revolted by the sickening sight of the liquefying meat, and finally recognising the taint within the ship for what it was - a charnel house of the warp: a spawning ground of the Immaterium.

Horus felt fresh resolve fill his limbs as he drew closer to the multiple blast doors that protected the bridge, more certain than ever that he must destroy Eugan Temba. He expected yet more legions of the warp-spawned things, but the way was eerily quiet, the silence punctuated only by the sounds of more gunfire (which he was now sure was coming from beyond the hull) and the patter of black water on his armour.

Horus made his way forward cautiously, brushing sparking cables from his path as, one by one, the sealed blast doors slowly rumbled open at his approach. The whole thing reeked of a trap, but nothing could deny him his vengeance now, and he pressed onwards.

Stepping onto the bridge of the Glory of Terra, Horus saw that its colonnaded immensity had been changed from a place of command to something else entirely. Mouldering banners hung from the highest reaches, with long dead corpses stitched into the torn fabric of each one. Even from here, Horus could see that they wore the lupine grey uniforms of the 63rd Expedition, and he wondered if these poor souls had stayed true to their oaths of loyalty.

'You will be avenged, my friends,' he whispered as he stepped further into the bridge.

The tiered workstations were smashed and broken, their inner workings ripped out and rewired in some bizarre new way, metres-thick bundles of coiled wire rising into the darkness of the arched ceiling.

Throbbing energy pulsed from the cables and Horus realised that he was looking at the source of the vox signal that had so perturbed Loken on the way in.

Indeed, he fancied he could still hear the words of that damned voice whispering on the air like a secret that would turn your tongue black were you to tell it.

Nurghleth, it hissed, over and over…

Then he realised that it wasn't some auditory echo from the ship's vox, but a whisper from a human throat.

Horus's eyes narrowed as he sought the source of the voice, his lip curling in revulsion as he saw the massively swollen figure of a man standing before the captain's throne. Little more than a heaving mass of corpulent flesh, a terrific stench of rank meat rose from his fleshy immensity.

Flying things with glossy black bodies infested every fold of his skin, and scraps of grey cloth were stuck to his green grey flesh, gold epaulettes glinting and silver frogging hanging limply over his massive belly.

One hand rested in the glutinous mess of an infected wound in his chest, while the other held a sword with a glitter-sheen like diamond.