Spittle frothed the red primarch’s lips. His oversized musculature, seemingly too tight for his vein-threaded skin, rippled. Thick ropes of sinew stood out on his neck. A scarred and war-beaten face, framed by the nest of cybernetic scalp-locks snaking back across his head, tensed as Angron’s eyes widened.

Farther down the slope, Vulkan gripped the haft of his hammer and went to meet his brother’s challenge.

Numeon saw it all, and almost urged his primarch to hold.

An arcing missile salvo from one of the traitor gun emplacements forced the Pyre captain’s attention skywards. He tracked the spear-headed missile all the way down, following its trajectory until it struck part of the slope between the two primarchs.

A firestorm lit the hillside, several tonnes of incendiary ordnance expressed in the expansive bloom of conflagration. It swept outwards in a turbulent wave, bathing the lower part of the slope in heat and flame. This was nothing compared to its epicentre. Firedrakes were immolated in that blast, blown apart and burned to ash in their Terminator armour.

A hundred dying sunsets faded from Numeon’s sight. Blinking back the savage afterglow he saw Vulkan wreathed in flames, but stepping from the blaze unharmed. The remaining Firedrakes gathered to him, tramping over the dead where they had to.

Badly burned, the Ravagers were still fighting. The Pyre Guard and some of Heka’tan’s men finished them before Numeon led the warriors after their lord. Varrun was limping. Atanarius clutched his side, but clung to his blade determinedly with one hand.

‘Are we whole, brothers?’ Numeon quickly asked.

Atanarius nodded.

Varrun gave a mocking laugh. ‘Perhaps we should look to increasing our ranks when this is over?’

Ganne came to his side, not supporting the veteran but keeping watch.

‘Are you my protector, brother?’ Varrun asked.

‘Not remotely,’ snarled Ganne, but didn’t leave him.

Igataron said nothing, and merely glowered. His eyes behind his retinal lenses always seemed to burn brighter than his brothers’.

Mauled as they had been by the World Eaters, Numeon knew that his warriors had suffered but would not stop until they were dead or the battle was over. But it was grievously attritional, and he was not ashamed to admit relief when he heard that the reinforcements coming in to make planetfall behind them.

Hundreds of landers and drop-pods choked the already suffocating sky, emblazoned with the iconography of the Alpha Legion, Iron Warriors, Word Bearers and Night Lords. Even the sight of Konrad Curze’s Legion gave Numeon hope that the battle could be won and Horus brought to heel at last.

Vulkan had seen the arrival of his brothers and their Legions too, though he gave no outward sign of relief or premature triumph. He merely watched impassively as the manifold shuttles touched down and the loyalists took up position on the edge of the depression. Of Angron, there was no sign. The firestorm had beaten him back, it seemed, and now with the arrival of four more Legions, the Lord of the Red Sands had ordered a retreat.

Grainy static preceded the opening of the vox-link. All the Pyre Guard heard it, too, though it was on Vulkan’s channel, the primarch’s view that there could be no secrets from his inner circle. Through the choppy return, the Gorgon’s voice thundered.

‘ The enemy is beaten!’

His anger was obvious, his desire for retribution palpable. Lord Manus wanted blood to salve his wounded pride.

‘See how they run from us!’ he continued, an eager fervour affecting him. ‘ Now we push on, let none escape our vengeance!’

Numeon exchanged a glance with Varrun. The veteran was badly wounded but able to fight on. Atanarius was also struggling, whilst Skatar’var stayed close to his brother Leodrakk on account of his injuries. With reinforcements ready to deploy, it made sense to fall back and consolidate. Pressing the advance now yielded only glory and profligate death.

Vulkan was impassive, betraying none of his thoughts as he allowed Corax to speak up.

‘ Hold, Ferrus! The victory may yet be ours, but let our allies earn their share of honour in this battle. We have achieved a great victory, but not without cost. My Legion is bloodied and torn, as is Vulkan’s…’

Again, the primarch kept his own counsel, as the Ravenlord concluded his speech.

‘ I cannot imagine yours has not shed a great deal of blood to carry us this far.’

Lord Manus was belligerent. ‘We are bloodied, but unbowed.’

Making the most of the enemy’s retreat and the brief cessation in the fighting, Vulkan chose that moment to give voice. ‘As are we all. We should take a moment to catch our breath and bind our wounds before again diving headlong into such terrible battle.’ The cost of which lay all around, clad in bloody green armour.

‘We must consolidate what we have won,’ Vulkan suggested, ‘and let our newly arrived brothers continue the fight while we regroup.’

But the Gorgon smelled blood and would not relent.

‘ No! The traitors are beaten and all it will take is one final push to destroy them utterly!’

Corax tried a last attempt at reason.

‘ Ferrus, do not do anything foolish! We have already won!’

It was to no avail, as the link to the Iron Hands’ primarch went dead.

‘Our brother has overmuch pride, Corvus,’ said Vulkan candidly.

‘ He will get himself killed.’

‘He is too tough for that,’ Vulkan said, but Numeon heard the lie in his words, the hollow tone of his voice.

‘ I won’t be dragged in with him, Vulkan. I won’t lead my sons into another meatgrinder for the sake of his pride.’

‘Then hope reinforcement reaches him quickly, for he won’t be dissuaded by you or I.’

‘ I am converging on the dropsite. Will I meet you there?’

Vulkan paused and it felt like the few seconds stretched into minutes before he gave his answer. Numeon was reminded of their words aboard the Fireforge, of Ferrus Manus’s wrath being his undoing, of the foreseen distemper in Horus and the profound disquiet about this very battle. They rose up in the Pyre Guard captain, threatening to choke him with their sense of foreboding.

‘Aye,’ said Vulkan at length. ‘We shall consolidate at the dropsite. Perhaps Ferrus will see sense and muster with us.’

‘ He won’t.’

‘No, you’re probably right.’ Vulkan ended the transmission. It was as if a mantle of grief lay about his shoulders, heavy with the burden of a fear that had been confirmed in what he’d just heard or felt. Numeon could not explain it.

‘Order all companies to fall back to the dropsite,’ Vulkan told him.

Numeon voxed down to K’gosi at once. The Pyroclasts had all but cleansed the trenches of the enemy, leaving the route back clear and open.

Whilst the retreat of Horus’s rebels was ragged and disorganised, the warriors of the XVIII and XIX Legions fell back in good order. Tanks returned to column, rumbling slowly but steadily back down the slope. The scorched trenches emptied as legionaries filed out in vast hosts, company banners still flying. They were battered but resolute. The dead and injured came with them, dragged or borne aloft by their still standing brothers. It was a great exodus, the black and green ocean of war retreating with the tide to leave the flotsam of their slain enemy behind it.

Most of the fortifications were destroyed. Huge sections of earthworks and spiked embankments lay open like rotting wounds. Bodies were impaled upon them, some clad in dusky white, others in arterial red or lurid purple. It was the evidence of fratricide a thousand times over, and it was this that Vulkan lingered behind to look upon before he quit the field.

‘This is not victory,’ he murmured. ‘It is death. It is bonds broken and bloody. And it shall mark us all for generations.’