All of this Numeon perceived in his peripheral vision and the frantic data inload from his retinal display. They all did.

‘To the ridge line,’ Vulkan shouted above the clamour, ‘and gain the higher ground!’

Artellus Numeon leads his warriors on Isstvan V

Withering fire hailed down on them from above, chugging from bunkers and murder-slits cut into the earth. Larger fortifications had been constructed farther up the bank, where it grew steep and was plugged with iron spikes meant for the disembowelling of tanks. In front of that was the first trench line, shouldered with sandbags and supported by jagged revetments, crowned with spools of razor-wire.

Shells pranging off his armour, the primarch took up the vanguard position, whilst his chasing Pyre Guard tried to keep pace. Numeon had no desire to see Vulkan’s back and would prefer to be his primarch’s shield than his rearguard. Roaring them to greater effort, he urged his six brothers to charge faster. They had yet to be measured against this battle’s fury, save for enduring its guns, and Numeon would have it that they close with their enemies before they were but smears on the black sand.

Behind the Pyre Guard, the stoic advance of the Pyroclasts struggled to keep up as they laid down sheets of burning promethium in front and to the flanks. The Terminator-armoured Firedrakes were also slipping back, unable to compete with the primarch’s speed, and Numeon began to see that there was a realistic danger of becoming estranged from the rest of the Legion.

But rather than suggest caution, he called in support to fill the gap instead.

‘Captain Nemetor,’ he rasped into his vox-feed, hoarse from shouting commands.

Above, the steady cascade of fire went on without cessation.

Two seconds of whispering static lapsed before Numeon got an answer.

‘ Commander…’

‘Lord Vulkan makes for the ridge line intent on clearing these trenches in advance of our tardy brother Legions’ arrival. I would see him reinforced.’

‘ Understood.’

Adding their strength to the spearhead the primarch was forging, the 15th Company reconnaissance took up fresh position. Their charge line would take them in alongside the Pyre Guard, able to maintain pace where the bulkier Firedrakes and Pyroclasts could not.

Numeon opened up a different channel. ‘Captain K’gosi, burn us a path to that first trench line. I want it aflame before we break it open.’

‘ Much closer and you’ll be the ones lit up and aflame,’ replied K’gosi, but gave the order.

‘Fire above!’ hollered Numeon, prompting the Pyre Guard and Nemetor’s company to crouch, still running, as a wave of flame streaked overhead and spilled into the edges of the first trench-works. The trammelling revetments burned, their spikes reduced to molten slag along with the razor-wire.

Ahead of the charging legionaries, Vulkan finally drew his sword. It shone in the visceral light that had stained the clouds above, a tongue of flame whipping down its edge. As if sensing that his Legion was losing him, he slowed but a fraction as the fire-blackened lip of the outermost trench drew close.

Hunkered within the partially sundered defences, the legionaries of the Death Guard brought guns to bear.

‘Into the fires of battle,’ Vulkan cried as a second flame-salvo spat from the advancing Pyroclasts. ‘Unto the anvil of war!’ he concluded, caught in the backwash of the flame storm but barrelling through it and into the trench.

Vulkan’s words still ringing in his ears and echoing from his own mouth, Numeon saw a Death Guard section leader rise up to challenge the Lord of Drakes. A hefty power maul crackled lightning in the formidable warrior’s left hand.

Vulkan split him in two before the blow could fall and smashed through the still-flailing corpse into his next opponent. Three more Death Guard warriors met similar fates before the Pyre Guard charged into the trench alongside their lord.

The XIV Legion were hardy fighters – the Salamanders had fought alongside them at Ibsen, but those days were gone and now allies had turned into enemies.

The flame storm and the ferocity of Vulkan’s attack had scattered the defenders but they were rallying quickly and now counter-attacked from three separate channels. Although the trench network was wide enough for three legionaries to stand abreast, the fighting was thick and fierce. A glaive swing took the head off one legionary, the dirty-white Maximus-pattern helmet spinning away into the churned up dust and smoke. More advanced through the gloom and Numeon angled his glaive to unleash a focused beam from his volkite, cutting through the traitor ranks.

For a few seconds his tunnel section was clear. Above him, the battle still sounded. Under his feet, the earth shook with every Titan salvo. But it had dulled and become almost a step removed as a strange sense of muted submersion fell upon Numeon. It gave the Pyre captain opportunity to gauge the status of his brothers.

Atanarius was advancing down the right-hand channel, reaping limbs and cleaving bodies with his double-handed power sword, as deadly as any of Dorn’s praetorians. Varrun followed a few paces behind the swordsman, laying down covering fire with his bolter. Igataron and Ganne went down the left spoke, storm shields locked in an impenetrable wedge, thunder hammers swinging. Leodrakk and Skatar’var stayed close to Numeon, the three of them holding the breach.

‘Such death…’ breathed Skatar’var, horrified at the slaughter.

‘Not ours, brother,’ Leodrakk reassured him.

Numeon envied a bond such as theirs, one he had never known himself, but now was not the time for such thoughts.

As the Death Guard poured in more troops from other parts of the trench-works, the eerie solemnity broke and battle resumed.

‘Should we follow?’ asked Leodrakk, gesturing to where Vulkan stormed up the middle trench.

Wilting before his charge, the defenders sensibly chose to hang back and harry the primarch with a welter of bolter fire. Meeting it head on, the primarch shrugged off the shell damage as the brass casings broke apart against his near-inviolable armour.

Shouting a fresh challenge, Vulkan threw himself into them.

Numeon shook his head in answer to Leodrakk.

‘We hold here and keep the breach open.’

To the left and right, the others were already in a staggered retreat. With the initial shock and awe of the assault now spent, the Death Guard were showing signs of recovery and the mettle Numeon knew they had in abundance. Droves of them came down from the upper slopes, filing into the trenches with sterner weapons than bolters.

Ganne took the burst from a plasma gun against his storm shield and he staggered, until Igataron hauled him up off one knee. Atanarius looked hard-pressed as he swung in a wide arc to avoid being overwhelmed. Varrun was falling back and urged his brother to do the same as the swordsman finally deigned to yield. Only Vulkan was undaunted and released a burst of flame from his gauntlet to cleanse the middle channel for a few seconds.

Reading the relative positions of their forces on his retinal display, Numeon ordered the others to regroup and rejoin the primarch. In their wake came Nemetor and the 15th, who had held on for further support just outside the trench. Coming up behind them were the Pyroclasts, surging left and right as the reconnaissance company pushed up the middle and went after the Pyre Guard, where heavier resistance was amassing.

Behind a flak-board palisade, a gun crew hurried to bring a mounted Tarantula to bear.

Leaping the barricade, Atanarius ran the first gunner through. A second drew a knife, but Atanarius blocked that and punched the legionary so hard that it cracked his faceplate. A third he decapitated, hacking around in a circle that ended in a downwards thrust to finish the warrior he had only stunned. It was over quickly, the cannon and its crew silenced before they could act. Igataron and Ganne repulsed a second squad who were moving in to an enfilading position from a narrow trench tributary spilling off the main course. Taking a flurry of snap shots against their storm shields, they then rushed the warriors and broke them with their thunder hammers.