Angron struck the summit of the hill as the Iron Warriors scattered. Steam poured into the air as the mud flashed to dust and then to glass. The daemon primarch rose, his movement a blur, the roar from his mouth shuddering through Argonis’ flesh.
He had asked Perturabo about this moment, about how he would deal with the creature that his brother had become.
‘As all conquest begins – with his weakness,’ Perturabo had replied, and had given no further answer. On the summit of the hill, with the fire-wind of Angron’s presence beating against his body and mind, Argonis could see no weakness in what the primarch had become. Perturabo stood inside the ring of his Iron Circle. The hammer Forgebreaker hung in his left hand, its head alight with cold lightning. The automata had turned so that their shields faced in, forming a circle around the two primarchs.
Beyond them, down the flanks of the hill, the walls of the Iron Warriors formation had driven through the World Eaters.
Volleys of bolt-rounds had ripped holes in the tide of howling legionaries. Tanks had ploughed through them, crushing bodies.
Shieldbearers had followed in their wake, forming new lines of blood-streaked plasteel. It was no longer a defence. It was strangulation. Channelled even as they killed, the World Eaters were now cut into pockets, contained. It would not hold, though.
‘This is madness,’ shouted Argonis.
‘It was always madness, Voice of Horus,’ said Forrix, the words edged with a cold chuckle. ‘Now it is just visible madness.’
On the hilltop, Angron reared to charge at Perturabo.
‘Fire,’ said Perturabo.
The Iron Circle obeyed. Fist-sized rounds tore into the daemon primarch. Explosions shattered against brass armour. Chunks of flesh and blood tore free, foaming into black ectoplasm as they fell. More units began to fire. Angron roared, his wings snapping wide as missiles and las-blasts tore them to tatters. The volume of fire was blinding, a lattice of angry light against the storm clouds. Angron came forwards, muscles pushing his form against the fire. Ichor drooled from gaping wounds, smoke and ashes shook from him. His flesh was remaking itself even as it was torn from him, swelling him so that he loomed above the crest of the hill, shivering with rage, radiating pain.
For an instant Argonis thought that the creature would fall. Then he seemed to shrink. Wounds closed. Armour glowed white and flowed into bullet holes. A high ringing noise filled Argonis’ head, blotting out the sound of gunfire and the roll of thunder.
He could feel nothing else, just the pain boring into the meat of his soul and burning down his nerves, and he knew that it would go on forever unless he stood, unless he poured it into the world as rage and let it coat his hands red.
The deluge of fire intensified, but Angron had taken a step forwards, and the blasts and shots were vanishing into the shadow of his shape. The daemon that had been a primarch charged.
Space folded as he moved. Features dissolved in a blur. His wings were slices of fast-moving shadow, his strides a flicker. The storm dragged after him. Lightning arced down, spearing through warriors and war machines. A tank exploded, its ammunition and fuel cooking off and punching its turret up into the air. A cluster of World Eaters became ash as power arced through them.
Blood cooked and rose in charring globules. Argonis watched, unable to move, unable to turn his mind to action. This was not simply a creature of destruction; it was a force of annihilation that was not meant to share the same realm as mortals.
He saw an axe form in Angron’s hand. Its edge was a slit of sharpened light. Reality tore as it cut. Smoke bled from the wound left behind its edge.
Perturabo was a statue of metal standing in the shadow of death. The axe cut. Perturabo moved aside. Even layered in armour and pistons, he was still faster than Argonis could dream, fast enough to almost avoid the blow. But nothing that was even half mortal could have avoided that cut. The axe struck his shoulder. White light blazed. For a second he could only see white, and then the neon scar burned onto the back of his eyes. He heard more blows fall, each one screaming louder than gunfire.
In the pit of his soul, he thought of all of the duties he had done Horus in the hope of clawing back the feeling of brotherhood that had been everything but was now just a memory. This would not just be failure. This would be death. He would end here, another heap of butchered meat on a world that was a graveyard of bones in a galaxy they had set ablaze. It all ended here: redemption, brotherhood and the lie of a higher purpose.
His sight cleared.
Perturabo still stood. Impossibly, the Lord of Iron stood.
Glowing scars marked the plates of his armour. Blood hissed as it ran over orange iron.
But he stood, and Forgebreaker was rising in his grasp, its head a comet as it swung.
Angron did not move to avoid the blow. He was swinging again, roaring, blood-slicked cables lashing around his head. Like all the other blows he had struck in the last second, it was faster than the eye that saw it. But Perturabo had timed his blow and slid it into the split-second gap as Angron swung back to strike again. The hammer struck. Forged by Fulgrim for the brother he had murdered, then given by Horus to Perturabo, it was a weapon that transcended even the craft put into its making.
The hammer head hit Angron’s chest. Brass armour shattered. The shock wave ripped outwards. Argonis felt it pass through him. Angron staggered.
Perturabo stepped forwards, the hammer swinging back in a blurred sheet of lighting.
Angron rammed forwards before Perturabo could strike, and now it was Perturabo going back, armour blackening as furnace flame breathed from Angron’s teeth. The axe struck again and again, blows that could end Titans falling. Fresh wounds opened in Perturabo’s armour. But still he stood.
‘You think I am weak,’ Perturabo’s voice boomed from the grille of his helm. Angron struck him twice again. Splinters of metal fell from the Lord of Iron as he staggered once more. ‘But you have grown weaker, Angron.’ The daemon primarch lashed a kick into Perturabo and struck once, twice, three times as the Lord of Iron stumbled back and crashed to his knees. ‘I have learnt. I have remade my strength. While you have sold yours out of despair.’
Argonis heard the words, heard the spite in them, the cold bitterness. There was something else there, too, something that made Argonis think of the knife duels in the dark warrens of Cthonia – cuts meant to goad, not kill.
Angron roared, and in the fraction of time that gave, Perturabo was on his feet, Forgebreaker moving faster than before. The air shook as its head struck and struck again, and there was blood on the baked mud of the ground beneath the two. Angron was scattering burning blood and broken armour. He lashed a fist at Perturabo. Claws tore the front from the Lord of Iron’s helm.
Perturabo’s skin was pale grey streaked with blood beneath. ‘You are weak,’ snarled Perturabo. ‘You are a slave. You were born a slave and a slave you remain.’
Angron cut Perturabo.
Argonis did not see it done, just the Lord of Iron suddenly still, a crimson trail running down his chest and glowing gashes smiling across his torso. Angron was striking again, but somehow he seemed to be shrinking, the edges of his shadow-and-flame bulk retreating like a wave from the shore. Perturabo struck back, and hammer and axe met.
‘Your strength flees,’ roared Perturabo. ‘It does not belong to you. It is your master’s, and the chain that keeps you throttles you. The threads of blood are thinning. The meal of slaughter will only keep you here long enough to see your bastard sons die.’
Beside Argonis, Forrix heard the words and keyed a control on his vox. Rounds began to hammer into the divided World Eaters. It had only been seconds since the Iron Warriors formation had entered its last configuration, and now Argonis saw that its weakness to further attack up the hill was a simple trade-off: vulnerability sold to allow for slaughter. In a few more minutes the World Eaters would have broken out of their corral, Argonis had no doubt, but they would not have that chance. Mortars thumped explosives into the kettled XII Legion. Cannons roared in overlapping sweeps. World Eaters fell, torn apart, their fury no more than bloody mist coughed from shredding lungs.
Angron turned towards the circle of automata surrounding them. His axe lashed out, burning gouges across the front of the circle of shields, again and again scoring deep.
‘Their skin is my skin,’ called Perturabo. ‘A gift of suffering at the hands of our brother.’ He was walking towards Angron, limping but hammer in hand. ‘You think that I would let your kind wield your weapons against me? I have taken their measure.’
Angron whirled, wings extending to carry him back at his brother. Perturabo raised his hands, weapon pods unfolding from his armoured shell. Angron’s tattered shadow wings beat.
Perturabo fired.
Streams of energy and exotic rounds blazed across the space between the two. Fire and explosions wreathed Angron. Ectoplasmic smoke billowed off him. His wings were broken frames of bone draped with scraps of skin. Perturabo came forwards as he kept up the fusillade, each step a slow thud of braced pistons.
‘They will die, here on this hill. They will die without striking a blow. All your best mongrel sons of slaughter. They will die, and your battered soul will watch as it sinks back into the dark.’
Angron was an outline now, a thing of threads remaking itself even as it was unravelled into smoke.
Imperial Fists 
