Something interrupted Bissot’s stream of fire below, snapping Atebe back to the present – she had been in the Killstate, her thoughts elsewhere as she killed automatically. Bissot being overrun meant their position was in danger of collapsing, which meant failure. Without interrupting her methodical extermination of individual targets, she called Bissot over the vox just as the volley gun growled back to life.

  ‘What’s going on down there, Bissot?’

  Bissot’s immediate answer was a series of grunts and snarls. ‘Just handling things manually,’ the gunner replied breathlessly. The volley gun’s report pulsed from below like an engine. ‘Some inventive soul has repurposed the servitors.’

  Atebe smirked. ‘You said you wanted a fight.’

  ‘Like I said, ask, and the God-Emperor provides,’ Bissot said, laughing. ‘I think I’m heading for an overheat or a burnout, though.’

  A fresh wave of militia troopers pushed forward behind the wave of servitors, dodging between the automata as they attempted to escape her volley gun’s unrelenting fire. These were not combat-hardened troops – they were sweating and wild-eyed, their fervent gazes clearly under the influence of narcotics. At their backs, officers executed any who showed a moment’s hesitation. One squad turned on their erstwhile leader, killing him and trampling his body into the floor as they fled the slaughter, but still others continued forward.

  ‘We only have to buy Norroll and the Tempestor time,’ Atebe said as a shot struck her left vambrace. Her long-las dipped, slipping from fingers left instantly numb by the impact, though the armour saved her arm.

  ‘Tadia?’

  Atebe adjusted her position, bracing her rifle on the back of her left arm. ‘Yes?’

  ‘Do you think my mother would be proud of me?’

  Looking down at the dozens of dead and wounded planetary militia troopers scattered across the blood-soaked floor of the concourse, Atebe grinned. ‘Yes, Favae. I think your mother would be very proud of you.’

  Bissot sighed quietly. ‘Good.’

  The volley gun seemed to laugh, its report bursting across the atrium with drawn-out, manic joy as the planetary militia troopers before her fell or fled. With a final burst, the weapon stopped firing, its indomitable spirit finally overburdened as its mechanisms failed. Singing unintelligibly, Bissot lunged forward into the attackers, swinging the red-hot barrel of her faithful volley gun like a heavy iron brand as she smote the impious below. She had affixed her bayonet and reaped a terrible tally as she clubbed, stabbed and stomped her enemies to death. She laughed as she killed, singing Imperial hymns as she battled free of the press of troopers attempting to claw at her, liberated by her own righteousness.

  Unwilling to risk hitting Bissot, Atebe fired into the troopers further back before they could close in and engage with the furious gunner. Dropping a pair, she risked a glance down.

  Bissot’s struggle was the most breathtakingly perfect melee Atebe had ever witnessed. A ray of sunlight had broken through the nuclear cloud above, streaming through the windows to form a halo of radiance about Bissot’s head, as if she had been suffused with a fragment of the Emperor’s manifold divinity. It took all Atebe’s willpower to tear her focus from the glorious slaughter below and release her awareness enough to re-enter the Killstate.

  The explosion beneath her registered but held no particular significance to Atebe as she swept the floor of hostiles. By the time the vibration of running footsteps on the stairway to the catwalk she lay upon snapped her partially from the Killstate, Atebe had lost all track of how many she had killed in the concourse below. She rolled, repositioning her long-las as she moved – at Atebe’s will, the target’s head came apart. Her sight picture adjusted, and she fired again, striking another trooper in the lower jaw. They flopped lifelessly to the ground a split second apart.

  Atebe took a deep breath, relaxing the Killstate just enough to exist in the present. She lifted her cheek from her rifle and listened to the screams of the wounded echoing through the concourse. An unidentifiable, high-pitched monotone squalled from close by, seemingly all around her. She ran her scope across the entire concourse, picking out movement here and there, but nothing that registered as a concerted threat against their position.

  ‘Bissot?’ she called. ‘Bissot, are you there?’

  The only reply she received was the thin sprinkling of static returned by the vox.

  She glanced at her vambrace, where the flatline of Bissot’s vitals stuttered beneath her own.

  She rose, keeping low as she stepped over the pair she had just killed, and descended the stairs. Thin tendrils of smoke twisted from the centre of a heap of the intermixed corpses of planetary militia troopers and servitors which lay spread across the blood-smeared floor. The bodies radiated from the centre, like the rays of a rising sun. Three of the casualties towards the far edge of the pile moved, and Atebe shot each one in quick succession. Holding her long-las with her right arm, she covered the area to the south as she used her left hand to dig through the pile of corpses at the centre for Bissot.

  She found the volley gunner lying face down beneath three enemies in a pool of blood, smoking beneath the exploded capacitor unit on her back. Lacking the Martyr’s Gift, which Daviland had already bestowed upon Phed, Bissot had manually overloaded her capacitors, killing the enemy as they finally managed to bring her down.

  ‘Your mother would be proud,’ Atebe said, rolling Bissot’s corpse over and lightly wiping away some of the blood smearing the gunner’s face.

  Beneath the blood, Bissot’s visage wore an expression of beatific serenity quite incompatible with the violence of her death. There was no pain in her closed eyes, and a soft, benign smile turned up the corners of her mouth. The strange radiance Atebe had noted before seemed yet to linger upon the volley gunner, and the sniper found herself returning Bissot’s gentle smile.

  The three levels Norroll and Traxel had to climb to reach Sky­­shield Four were easier to access than they had anticipated. The air was filled with the reek of promethium smoke and the tang of heavy metals, growing thicker and more opaque with each storey they climbed. Administratum adepts, labourers and servitors blocked their path. Some resisted.

  Norroll stopped counting how many he had killed at thirty, and it had become steadily more monotonous since. The corridors were awash with blood and viscera as he and Traxel butchered anyone foolish enough to stand in their way, irrespective of whether they were attacking or fleeing. There was a sense of retribution to the massacre, Norroll thought, a final comeuppance for those who had turned from the Emperor’s light, but it was far from satisfying.

  Smoke filled the stairwell, obscuring their sight as they rushed to the third level. Their respirators were still sufficient to filter out the toxic fumes.

  Clearing the hatchway at the top of the stairwell, the Scions were fired upon by a handful of grey-robed adepts choking on the smoke. A bullet flattened against Traxel’s armour below the sternum, and the Tempestor decapitated the shooter for his accuracy. Norroll cut down two more, then another as Traxel wrenched his chainsword free of a ribcage. As the ruptured corpse dropped limply to the ground, they found themselves unopposed, their path to Skyshield Four finally open.

  Six servitors, armed with high-pressure hoses connected to the bulky tanks of fire retardant mounted to their backs, stumped towards the hatchway. Utterly indifferent to the Scions, the servitors babbled to themselves as they halted at the platform’s closed hatch, unsure how to proceed when they discovered their way blocked. Traxel and Norroll passed them by and accessed the door’s controls.

  The hatch opened with the smooth hiss of well-maintained hydraulics, and the Tempestus Scions shoved past the firefighter servitors and onto the landing platform.

  The Valkyrie’s tail was twisted up over the back of the fuselage while the nose of the gunship was flattened into the ground – despite his aircraft’s being dead in the air, Sandeborn had somehow managed to nosedive it directly onto his target. The heat of the blaze consuming the gunship had further warped its frame, causing it to buckle beneath its own weight.

  The fire’s heat was nearly unbearable, singeing the hair from skin where the Scions’ fatigues had been torn open. Traxel and Norroll studied the flaming wreckage, searching for evidence that their quarry had somehow managed to survive.

  ‘It could be hours before this has burned out enough for us to mount a proper search,’ Norroll said.

  Nodding, Traxel sighed. ‘I’m debating whether it’s better to let the fire do its work or let the servitors do their jobs so we can get on with it.’

  As if in answer, the framework towards the front of the conflagration crumpled with a shriek of twisting metal. An armoured panel collapsed, ringing from the landing platform’s deck as a flame-wreathed figure rose from the heart of the pyre. The Iron Warrior pushed through the wreckage, tearing through it with his bare hands or smashing it aside with his servo-arm.

  Dropping his damaged lascannon to the deck as he extricated himself, the Heretic Astartes drew his bolt pistol from its hip holster, taking aim on the momentarily dumbfounded Scions.

  ‘From Iron cometh strength!’ the Space Marine shouted, firing his bolt pistol. The round glanced from Norroll’s helmet, knocking him from his feet.

  ‘From strength cometh will,’ the Iron Warrior continued, flames wreathing him like some malevolent fiend stepping free of the inferno. Traxel dodged as he fired another shot. The round creased the Tempestor’s left tricep and detonated in one of the servitors behind him.

  ‘From will cometh faith.’ Zelazko’s left leg was clearly injured, but he was moving now, dragging his foot as he approached the Scions. Another round burst against the rear of Traxel’s right pauldron in a puff of shrapnel.

  ‘From faith cometh honour.’ Two rounds spanged from the platform where Norroll had been knocked prone a split second before. ‘From honour cometh Iron.’

  Hobbling towards the Scions, Zelazko drew his chainsword and thumbed the ignition.

  ‘This is the Unbreakable Litany,’ the Iron Warrior bellowed over the chainsword’s roar. ‘May it ever be so.’

  XXIV

  Zelazko burst from the smoke, his armour smouldering and soot black from the flames which had engulfed him. His chainsword snarled in his grip, the hungry animus of the blade’s corrupted spirit clamouring in its keenness to feast upon the Scions’ flesh and blood. Even limping, the Iron Warrior was incongruously fast for his bulk – the dichotomy between expectation and reality stymied Norroll’s ability to understand what he was seeing as the transhuman charged them.

  Norroll’s forebrain worked on the sheer improbability of the situation he found himself in, rather than focusing on the animal part of his brain screaming for him to flee. Statistically speaking, any given Imperial citizen’s chance of ever encountering even a single Adeptus Astartes across the breadth of the galaxy in a single lifetime fell so far into the realm of extreme ­improbability that it should be impossible. The one charging him was the third he had encountered in under two weeks, and before that there had been the ones on Tecerriot. Traitors all.

  It was comforting to focus on such trivialities in moments like this – far better than accepting the reality that there was simply no way he would ever be fast enough to avoid the avatar of death charging headlong towards him.

  Traxel’s chainsword struck the Iron Warrior’s aside in mid-swing, a direct hit to the side of Zelazko’s blade that turned the killing blow into a glance that chewed down the length of Norroll’s left pauldron, spitting armour plate and ceramite. With the grace of a born duellist, Traxel diverted the energy of his swing, angling his snarling blade to glance up the length of the Heretic Astartes’ weapon to strike at Zelazko’s less-armoured throat.

  Zelazko swayed backwards, his artificer-crafted armour’s fibre-bundle musculature and servomotor augmentation in the joints granting him an impossible level of dexterity, enabling him to simply avoid the chainsword’s spinning teeth. Flicking his own chainblade around, he slapped Traxel’s weapon aside with a casual upward strike, then punched the Tempestor in the side of the head with his free hand.

  The blow spun Traxel into the air, cratering his helm and sending him careening backwards. Against an unarmoured opponent it surely would have been a decapitating strike, but the ablative microlayers in his helm held, distributing the force about the whole of his head. The Tempestor flailed as he slid to a halt, struggling for orientation.

  Acting on instinct, Norroll stabbed upwards, driving his right monoblade into the softer, ribbed armour of Zelazko’s armpit. The Iron Warrior’s servo-arm swung out from above, smashing into Norroll’s flank and crushing his carapace. Pain flared in his side as his ribs buckled and the world spun around him. Norroll twisted through space, tumbling over the side of the landing platform. He reached out, desperately grasping at a section of raised blast shielding at the Skyshield’s edge.

  His fingers hooked on a length of power cabling on the underside of the platform, narrowly arresting his fall. Norroll dangled beneath the Skyshield, swaying in the wind near the upper reaches of the Vanness Tether’s mid-levels. The outskirts of Vytrum spread out nearly a mile beneath him, entirely obscured by the boiling haze of dust kicked up by the blast wave of the explosion above.

  Taking a deep breath, Norroll pulled himself up with one arm, pushing away the searing pain in his ribs to reach out and take hold of the cabling with his other hand. He kicked a foot over it, fumbling for a handhold on the platform above.

  He had lost both monoblades when the Iron Warrior struck him, and doubted whether his laspistol would prove sufficient to bring the Traitor Astartes down. Carefully, he managed to secure a fingerhold against the blast shielding, balancing on the cable as he prepared to free-climb back up to the platform.

  The thump-and-hiss discharge of Traxel’s plasma pistol quickened his pace. Norroll dug his fingertips into the tiny lip of metal at the bottom of the shielding and pulled, feet swinging beneath him as he scrambled upwards and secured a grip on one of the small shrines to the Machine God decorating the blast shielding at regular intervals. He heaved his right foot onto the bottom lip of the platform and rose, stabilising himself enough that he could look over the shield.

  No sooner had Norroll managed to peek over the barrier than his right foot slipped, dropping him down and nearly pitching him from the Skyshield. He snatched reflexively for a handhold, halting his fall as his fingers closed around the blast shield’s upper lip. Grunting, he struggled to right himself. He strained to climb over it, his battered and fatigued body protesting as he managed to hoist himself high enough to look over the edge once again.

  The Heretic Astartes clutched Traxel in his servo-arm, holding the Tempestor inverted mere inches before the soot-blackened skull visage of his battle helm. Arms pinned in the servo-arm’s clawlike grip, Traxel spat a wad of bloody phlegm onto the Iron Warrior’s visor as he struggled to free himself. Blood dripped down the right side of Traxel’s head, sheeting from where his ear had been torn off when the Iron Warrior had forcibly removed his helmet.

  The Tempestor’s plasma pistol lay at Zelazko’s feet, while his chainsword was on the deck of the landing platform, several feet in front of where Norroll scrambled over the defence barrier.

  To the west, the remains of the Devourer-class drop-ship smashed down onto the capitol building, ejecting a plume of flame as it eradicated the structure. The drop-ship’s blackened corpse teetered for a few seconds before collapsing, the vessel’s fuselage seeming to wilt as it buckled and collapsed over the length of the capitol mall in a titanic shriek of protesting metal.

  Distracted by the fury of the drop-ship’s destruction, Zelazko glanced away from his captive.

  Traxel wrenched his left arm free of the servo-arm’s grip and snatched the last krak grenade from his belt, priming the explosive and stuffing it between the Iron Warrior’s gorget and helm.

  Driven by some atavistic impulse, the servo-arm snapped open, dropping Traxel head first to the deck. Zelazko clutched frantically at the grenade wedged behind his gorget, fumbling at it with scrabbling fingers before it exploded in his hand.

  The Traitor Astartes swayed, the gyroscopic stabilisers in his boots snarling as they struggled to keep him upright. A plume of smoke twisted from between his shoulders, obscuring much of his head. Crippled by the blast, his servo-arm dangled limply from its mount on his power armour’s backpack. He reached for his helmet with his right hand, staring bemusedly at his mangled limb before seeming to realise that the extremity was missing. He released his chainsword from his left hand and pulled the ruptured battle helm from his head, dropping it heavily to the ground.

  Traxel grabbed at his plasma pistol, his fingers wrapping around the grip before Zelazko planted a hard kick into the side of his head, sending the Tempestor rolling and skidding across the deck.

  Norroll clambered over the blast shielding, firing his laspistol on the move before slipping face first onto the platform. The shot went wide, streaking past the bleeding nub of the Iron Warrior’s right ear, though it managed to draw the Heretic Astartes’ attention from the Tempestor.

  Zelazko hurled himself at Norroll. His injuries made him clumsy, and he collapsed onto his chest with a peal of metal on metal. He was up in an instant, propelled forward by inhumanly responsive reflexes.

  The delay was enough. Fuelled by desperation and adrenaline, Norroll snatched up Traxel’s chainsword, thumbing the activator stud and swinging for Zelazko’s neck as he shambled towards the limping Space Marine.