Fulgrim reversed the blade and held its fiery tip against his body, the edge blackening his hands and burning the skin through the rents torn in his armour.

To end things now would be the easiest thing in trie world, to take away the guilt and wash the pain away in a sharp trirust of steel into his vitals. Fulgrim gripped the sword tightly, drawing blood from his palms where the blade's edge sliced his skin.

No, noble suicide is not for the likes of you, Fulgrim.

'Then what?' howled Fulgrim, hurling away the sword his brother had forged.

Oblivion: the sweet emptiness of eternal peace. I can grant you what you crave… an end to guilt and pain.

Fulgrim rose to his feet and stood tall beneath the storm wracked clouds of Isstvan V, his once beautiful face streaked with tears, and his pristine armour stained with the blood of his beloved brother.

Fulgrim lifted his hands and looked at the blood there.

'Oblivion,' he said, his voice hoarse. 'Yes, I crave the boon of nothingness.'

Then leave yourself open to me and I will put an end to it all.

Fulgrim took a last look around. The grim-faced warriors who had foolishly thrown in their lot with the Warmaster: Marius, Julius and thousands more were damned, and they could not see it.

All around him, he could hear the sounds of the future, of warfare and death. The thought that he shared the guilt of the destruction of the Emperor's dream was the greatest shame and sorrow he had ever known.

An end to it all would be a blessed relief.

'Oblivion,' he whispered as he dosed his eyes. 'Do it. End me.'

The barriers in Fulgrim's mind dropped and he felt the elation of a creature older than time as it poured into the void in his soul. No sooner had its touch claimed his flesh for its own than he knew he had made the worst mistake of his life.

Fulgrim screamed as he fought to keep it out, but it was already too late.

His consciousness was crushed into the dark, unused corners of his mind, forever to be a mute witness to the havoc wrought by his body's new master.

One moment Fulgrim was a primarch, one of the Emperor's Children, the next he was a thing of Chaos.

Lesser troops would have given up and accepted their fate in the face of such overwhelming opposition, but the warriors of the Salamanders and Raven Guard were Astartes. So they fought like never before, knowing their doom was at hand, and desiring to make the traitors pay in blood for every one of their number that fell.

Caught between two armies, the first wave of the loyalist forces was being systematically massacred. Unrelenting gunfire from the Iron Warriors at the drop-site, and the resurgent forces along the Urgall Depression crushed the Salamanders and Raven Guard in a terrifying vice, and cut them to pieces in a murderous storm of fire and blood.

Warriors of the Alpha Legion and Word Bearers followed their leaders onto the black plains of Isstvan V, their guns blazing and their chainswords bright as they cast off the last remnants of their loyalty to the Emperor and turned their weapons on their brothers.

The Dies Irae killed scores with every shot of its mighty weaponry, striding like a giant daemon of legend through the benighted slaughter. White-hot fire blossomed amongst the loyalists and killing flames sawed across the black desert, vaporising men and turning sand to glass. Traitor tanks roared from the Urgall Hills, weapons blazing and crashing the wounded beneath their tracks. The Iron Hands were lost, the fate of their primarch a mystery as his last known position was overrun by hordes of screaming enemy warriors.

Let slip from his false retreat, Angron carved a bloody path through the loyalists, his swords reaping a bloody tally through the ranks of his enemies. The Red Angel fought in a barbaric frenzy, his mind lost to all but the killing rage that drove his blades. His warriors hacked and chopped their foes like butchers, in a killing frenzy of berserk rages, slathering their armour in the blood of the fallen.

If the noise of battle had been incredible before, it was deafening now, no voices heard that were not screams of pain or hate. Individual sounds were lost amid the constant roar of gunfire and rambling explosions, melding into one long immense howl of murder. What had begun as a battle had become a massacre, each pocket of loyalist resistance gunned down with overwhelming superiority of fire, before the shredded survivors were hacked apart with bloody chainswords.

Mortarion harvested loyalists with great sweeps of his scythe, his ragged cloak billowing in the hot winds of the battlefield's fires, as the Death Guard crashed their foes beneath the relentless pounding of marching feet and the disciplined volleys of gunfire.

At the forefront of the Emperor's Children, Lord Commander Eidolon and the swordsman Lucius led a contingent of their warriors into the heart of the enemy, killing with wondrous displays of bladework and howling shrieks of raw sonic power. The swordsman danced through the battle, his Terran blade carving a screaming, bloody path as he laughed in time with music only he could hear.

Marius Vairosean and his orchestra of damnation ploughed the bloody sand with their terrifying harmonics, ripping open flesh and metal with shrieking chords and howling scales. In contrast, Julius Kaesoron took little part in the fighting, expending his energies in the mutilation and defilement of the corpses left in his brother's wake. Trophies of flesh hung from his armour, each violation he wreaked on the flesh of the enemy more extreme than the last.

Apothecary Fabius picked his way through the carnage like a vulture, pausing here and there at fallen Astartes to perform some gruesome extraction. A coterie of warriors protected him and hideous homunculi assisted him in his loathsome labours, the fruits of which were borne behind them in a vile procession of bloodstained organ bearers.

Fulgrim was nowhere to be seen, the magnificent primarch lost amid the destruction of the Iron Hands' Morlocks, but even without him, his warriors fought with savage and exquisite glee.

With victory in his grasp, the Warmaster took to the field of battle, surrounded by Falkus Kibre and his Justaerin Terminators. The remnants of Horus's Mournival fought alongside him, the Warmaster's magnificent black armour and amber chest adornment gleaming bloody in the firelight.

The killing fields of Isstvan V ran red with the blood of the loyalists, their brave attempt to halt the rebellion of Horus little more than ragged flesh and blood that fought for the last shreds of honour left to them.

Here and there, fierce resistance overcame the traitorous forces and desperate bands of heroes fought their way clear of the trap, dragging their wounded with them towards the few surviving drop-ships.

A band of Raven Guard smashed through a cordon of Emperor's Children who shrieked in orgasmic pleasure as they were cut down, too immersed in the sensations of their own pain and death to fight back. A black-armoured captain led the breakout, fighting his way towards a miraculously undamaged Thunderhawk as his warriors bore the grievously wounded body of their primarch towards escape.

Of Vulkan there was no sign, his warriors cut off and surrounded by the Night Lords and Alpha Legion. Gales of bolter fire hammered the brave warriors of Nocturne and obliterated them. Not all the Salamanders were so cruelly slaughtered, others following the Raven Guard's example and battling their way to their aircraft and the hope of escape.

The few remaining Iron Hands, bereft of their primarch's leadership, banded together with the Salamanders and a brave few managed to break out of the hideous massacre, but such successes were the merest fraction of the battle.