His exquisite armour was a work of art in purple and gold, bearing many new embellishments and

finery with a flowing, fur-lined cape swathing his body. More than ever, Horus thought Fulgrim looked less like a warrior and more like a rake or libertine. His brother's long white hair was pulled back in an elaborate pattern of plaits and his pale cheeks were lightly marked with what appeared to be the beginnings of tattoos.

'Ferrus Manus is a dull fool who would not listen to reason,’ said Fulgrim. 'Even the mention of the Mechanicum's pledge did not-'

You swore to me that you could sway him! The Iron Hands were essential to my plans. I planned Isstvan III with your assurance that Ferrus Manus would join us. Now I find that I have yet another enemy to contend with. A great many of our Astartes will die because of this, Fulgrim,’

'What would you have had me do, Warmaster?' smiled Fulgrim, and Horus wondered where this new, sly mocking tone had come from. 'His will was stronger than I anticipated,’

'Or you simply had an inflated opinion of your own abilities,’

'Would you have me kill our brother, Warmaster?' asked Fulgrim.

'Perhaps I will,’ replied Horus unmoved. 'It would be better than leaving him to roam free to destroy our plans. As it is he could reach the Emperor or one of the other primarchs and bring them all down on our heads before we are ready,’

Then if you are quite finished with me, I shall return to my Legion,’ said Fulgrim, turning away.

Horus felt his choler rise at Fulgrim's infuriating tone and said, 'No, you will not. I have another task for you. I am sending you to Isstvan V. With all that has happened, the Emperor's response is likely to arrive more quickly than anticipated and we must be prepared for it. Take a detail of Emperor's Children to the alien fortresses there and prepare it for the final phase of the Isstvan operation.'

Fulgrim recoiled in disgust. 'You would consign me to a role little better than a castellan, as some prosaic housekeeper making it ready for your grand entrance? Why not send for Perturabo? This kind of thing is more to his liking.'

'Perturabo has his own role to play,' said Horus. 'Even now he prepares to lay waste to his home world in my name. We shall be hearing more of our bitter brother very soon. Have no fear of that.'

'Then give this task to Mortarion. His grimy footsloggers will relish such an opportunity to muddy their hands for you!' spat Fulgrim. 'My Legion was the chosen of the Emperor in the years when he still deserved our service. I am the most glorious of his heroes and the right hand of this new Crusade. This is... this is a betrayal of the very principles for which I chose to join you, Horus!'

'Betrayal?' said Horus, his voice low and dangerous. 'A strong word, Fulgrim. Betrayal is what the Emperor forced upon us when he abandoned the galaxy to pursue his quest for godhood and gave over the conquests of our Crusade to scriveners and bureaucrats. Is that the charge you would level

at me now, to my face, here on the bridge of my own ship?'

Fulgrim took a step back, his anger fading, but his eyes alight with the excitement of the confrontation. 'Perhaps I do, Horus. Perhaps someone needs to tell you a few home truths now that your precious Mournival is no more.'

That sword,’ said Horus, indicating the venom-sheened weapon that hung low at Fulgrim's waist. 'I gave you that blade as a symbol of my trust in you, Fulgrim. We alone know the true power that lies within it. That weapon almost killed me and yet I gave it away. Do you think I would give such a weapon to one I do not trust?'

'No, Warmaster,’ said Fulgrim.

'Exactly. The Isstvan V phase of my plan is the most critical,' said Horus, stoking the dangerous embers of Fulgrim's ego. 'Even more so than what is happening below us. I can entrust it to no other. You must go to Isstvan V, my brother. All depends on its success,’

For a long, frightening moment, violent potential crackled between Horus and the primarch of the Emperor's Children.

Fulgrim laughed and said, 'Now you flatter me, hoping my ego will coerce me into obeying your orders,’

'Is it working?' asked Horus as the tension drained away.

Yes,’ admitted Fulgrim. Very well, the Warmas-ter's will be done. I will go to Isstvan V,’

'Eidolon will stay in command of the Emperor's Children until we join you at Isstvan V,’ said Horus and Fulgrim nodded.

'He will relish the chance to prove himself further,’ said Fulgrim.

'Now leave me, Fulgrim,’ said Horus, 'You have work to do,’

SIXTEEN

Enemy within

The Eightfold Path

Honour must be satisfied

APOTHECARY VADDON FOUGHT to save Casto's life. The upper half of the warrior's armour had been removed and his bare torso was disfigured by a gory wound, flaps of skin and chunks of muscle blown aside like the petals of a bloody flower by an exploding bolter round.

'Pressure!' said Vaddon as he flicked over the settings on his narthecium gauntlet. Scalpels and syringes cycled as Brother Mathridon, an Emperor's Children Astartes who had lost a hand in the earlier fighting and served as Vaddon's assistant, kept pressure on the wound. Casto bucked underneath him, his teeth gritted against.pain that would kill anyone but an Astartes.

Vaddon selected a syringe and pushed it into Casto's neck. The vial mounted on the gauntlet

emptied, pumping Casto's system with stimulants to keep his heart forcing blood around his ruptured organs. Casto shook, nearly snapping the needle.

'Hold him still,' snapped Vaddon.

'Yes,' said a voice behind them. 'Hold him still. It will make it easier to kill him.'

Vaddon's head snapped up and he saw a warrior clad in the armour of an Emperor's Children lord commander. He carried an enormous hammer, purple arcs of energy playing around its massive head. Behind the warrior, Vaddon could see a score of Emperor's Children in purple and gold finery, their armour sheened with lapping powder and oil.

Instantly, he knew that these were no loyalists and felt a cold hand clutch at his chest as he saw that they were undone.

'Who are you?' demanded Vaddon, though he knew the answer already.

'I am your death, traitor!' said Eidolon, swinging his hammer and crushing Vaddon's skull with one blow.

HUNDREDS OF EMPEROR'S Children streamed into the palace from the east, on a tide of fire and blood. They fell upon the wounded first, Eidolon himself butchering those who lay waiting for Vaddon's ministrations, taking particular relish in killing the loyalist Emperor's Children he found there. The warriors of his Chapter swarmed through the palace around him, the defenders discovering to their horror that their flank had somehow been

turned and that more and more of the traitors were pouring into the palace.

Within moments, the last battle had begun. The loyalists turned from their defences and faced the Emperor's Children. Assault Marines' jump packs gunned them across ruined domes to crash into Eidolon's assault units. Heavy weapons troopers and scout snipers amongst the ruined battlements shot down into the enemy, swapping tremendous volleys of fire across the shattered domes.

It was a battle without lines or direction as the fighting spilled into the heart of the Precentor's Palace. Each Astartes became an army of his own as all order broke down and every warrior fought alone against the enemies that surrounded him. Emperor's Children jetbikes screamed insanely through the precincts of the palace and ripped crazed circuits around the domes, spraying fire into the Astartes battling below them.

Dreadnoughts tore up chunks of fallen masonry with their mighty fists and hurled them at the loyalists holding the barricades against which so many of their foes had died only a short while before.