Horus dropped to his knees in anger and sorrow as he saw the slumped corpse of an Astartes warrior sprawled before the decayed splendour of the bloated figure.

Verulam Moy, his neck obviously broken and his sightless eyes fixed upon the decaying corpses hanging from the banners.

Even before Horus lifted his gaze to Moy's killer, he knew who it would be: Eugan Temba…

The Betrayer.

Loken could scarcely remember a fight where he and his warriors had expended all their ammunition. Each Astartes carried enough shells to sustain them for most types of engagement, since no shot was wasted and each target would normally fall to a single bolt.

The ammo hoppers were back at the drop site and there was no way they could get through to them. The Warmaster's resolute advance had seen to that.

Loken's full capacity of bolter rounds had long been expended, and he was thankful for Aximand's insistence on subsonic rounds, as they made satisfyingly lethal explosions within the bodies of the dead things.

'Throne, don't they ever stop?' gasped Torgaddon. 'I must have killed a hundred or more of the damned things.'

'You probably keep killing the same one,' replied Loken, shaking his sword free of grey matter. 'If you don't destroy the head, they get back up again. I've cut down half a dozen or more with bolter wounds in them.'

Torgaddon nodded and said, 'Hold on, the Legio's coming again.'

Loken gripped onto a more solid piece of debris, as the Titans began yet another deadly strafing run through the mass of rotted monsters. Like the monstrous giants said to haunt the mists of Barbarus, the Titans emerged from the fog with fists of thunder and fire. Wet explosions mushroomed from the swamp as high explosives hurled the cadavers into the air and the crashing steps of the mighty war machines crashed them to ooze beneath their hammer-blow footsteps.

The very air thrummed with the vibrations of the Titans' attack, avalanches of debris and mud sliding from the Glory of Terra with each explosion and titanic footstep. The dead things had gained the slopes of rubble and detritus that led into the starship three times; and three times had they sent them back, first with gunfire, and, when the ammunition had ran out, with blades and brute strength. Each time they killed hundreds of their enemies, but each time a handful of Astartes was dragged down and pulled beneath the waters of the swamp.

Under normal circumstances, the Astartes would have had no trouble in dealing with these abominations, but with the Warmaster's fate unknown they were brittle and on edge, unable to think or fight with their customary ferocity. Loken knew exactly what they were feeling, because he felt it too.

Unable to raise the Warmaster, Aximand or Abaddon, the warriors outside the hulk were left paralysed and in disarray without their beloved leader.

'Temba,' said the Warmaster, rising to his feet and marching towards his erstwhile planetary governor. With each step, he saw further evidence of Eugan Temba's treachery, clotted blood on the edge of his sword and a fierce grin of anticipation. Where once had been the loyal and upright follower, Horus now saw only a filthy traitor who deserved the most painful of deaths. A fell light grew around Temba, further revealing the corruption of his flesh, and Horus knew that nothing of his former friend was left in the diseased shell that stood before him.

Horus wondered if this was what Loken had experienced beneath the mountains of Sixty-Three Nineteen: the horror of a former comrade succumbing to the warp. Horus had known of the bad blood between Jubal and Loken, now understanding that such enmity, however trivial, had been the chink in Jubal's armour by which the warp had taken him.

What flaw had been Temba's undoing? Pride, ambition, jealousy?

The bloated monster that had once been Eugan Temba looked up from the corpse of Verulam Moy and smiled, thoroughly pleased with its work.

'Warmaster,' said Temba, each syllable glottal and wet, as though spoken through water.

'Do not dare to address me by such a tide, abomination.'

'Abomination?' hissed Temba, shaking his head. 'Don't you recognise me?'

'No,' said Horus. 'You're not Temba, you're warp-spawned filth, and I'm here to kill you.'

'You are wrong, Warmaster,' it laughed. 'I am Temba. The so-called friend you left behind. I am Temba, the loyal follower of Horus you left to rot on this backwater world while you went on to glory.'

Horus approached the dais of the captain's throne and dragged his eyes from Temba to the body of Verulam Moy. Blood streamed from a terrible wound in his side, pumping energetically onto the stained floor of the bridge. The flesh of his throat was purple and black, a lump of broken bone pushing at the bruised skin where his neck had been snapped.

'A pity about Moy,' said Temba. 'He would have been a fine convert.'

'Don't say his name,' warned Horus. 'You are not fit to give it voice.'

'If it consoles you, he was loyal until the end. I offered him a place at my side, with the power of Nurghleth filling his veins with its immortal necrosis, but he refused. He felt the need to try to kill me, foolish really. The power of the warp fills me and he had no chance at all, but that didn't stop him. Admirable loyalty, even if it was misplaced.'

Horus placed a foot on the first step of the dais, his golden sword held out before him, his fury at this beast drowning out all other concerns. All he wanted to do was throttle the life from this treacherous bastard with his bare hands, but he retained enough sense to know that if Moy had been killed with such apparent ease, then he would be a fool to discard his weapon.

'We don't have to be enemies, Horus,' said Temba. 'You have no idea of the power of the warp, old friend. It is like nothing we ever saw before. It's beautiful really'

'It is power,' agreed Horus, climbing another step, 'elemental and uncontrollable and therefore not to be trusted.'

'Elemental? Perhaps, but it is far more than that,' said Temba. 'It seethes with life, with ambition and desire. You think it's a wasteland of raging energy that you bend to your will, but you have no idea of the power that lies there: the power to dominate, to control and to rule.'

'I have no desire for such things,' said Horus.

'You lie,' giggled Temba. 'I can see it in your eyes, old friend. Your ambition is a potent thing, Horus. Do not be afraid of it. Embrace it and we will not be enemies, we will be allies, embarking upon a course that will see us masters of the galaxy.'

'This galaxy already has a master, Temba. He is called the Emperor.'

'Then where is he? He blundered across the cosmos in the manner of the barbarian tribes of ancient Terra, destroying anyone who would not submit to his will, and then left you to pick up the pieces. What manner of leader is that? He is but a tyrant by another name.'

Horus took another step, and was almost at the top of the dais, almost within striking distance of this traitor who dared to profane the name of the Emperor.

'Think about it, Horus,' urged Temba. 'The whole history of the galaxy has been the gradual realisation that events do not happen in an arbitrary manner, but that they reflect an underlying destiny. That destiny is Chaos.'

'Chaos?'

'Yes!' shouted Temba. 'Say it again, my friend. Chaos is the first power in the universe and it will be the last. When the first ape creatures bashed each other's brains out with bones, or cried to the heavens in the death throes of plague, they fed and nurtured Chaos. The blissful release of excess and the glee of intrigue - all is grist for the soul mills of Chaos. So long as Man endures, so too does Chaos.'