Helos Majoris defended again from Tyranid Menace

In the Hadron Expanse, the closing months of 011.025.M42 brought renewed turmoil as the Tyranid threat continued to swell unchecked across the Rifts of Hecate. Most factions had already begun a hasty and disorganised withdrawal from the region, abandoning worlds to the shadow of Hive Fleet Poseidon. In this chaotic vacuum, the Imperium stood out as the only power still mounting coherent resistance.

The Defence of Heloris Majoris

The strategic bastion of Heloris Majoris, long a lynchpin of Imperial operations deep within the Rifts, once again found itself targeted by Tyranid bio-fleets probing for weakness. A fresh landing of xenos organisms made planetfall in an attempt to overwhelm the fortress-world’s outer defences.

However, this time the Imperium reacted with decisive speed. A rapid strike by the Space Wolves intercepted the Tyranid vanguard. The Sons of Russ tore into the alien swarms with characteristic ferocity, their counter-assault shattering the landing force before it could take root. Within hours, the bioforms were purged, and Heloris Majoris stood secure once more.

Strategic Dispute Within Imperial Command

Yet the defence of the world reignited long-standing divisions within Imperial High Command regarding the future of the campaign in the Expanse.

The Lord Sector Commander argued for a controlled withdrawal, abandoning exposed holdings and consolidating the Imperium’s strength at the critical choke point of the Hecate Gap. He insisted that worlds such as Haven and Ergura’s Fall could form a defensible redoubt should the Tyranids surge further outward.

General Maximus, by contrast, urged continued expansion and exploitation within the Rifts. He insisted that controlling worlds like Heloris Majoris provided not only valuable resources but strategic depth. His critics, however, suspected his motives. Rumours whispered through command chambers that Maximus sought personal glory more than sound military outcomes.

For now, Maximus’ argument prevailed. Heloris Majoris remained in Imperial hands, held through Space Wolf valour and political inertia—but the question of whether the Imperium should stand or fall back in the Expanse remained bitterly unresolved.

The Tyranid threat was growing, and every passing month narrowed the margin for error.

Xenos infestation worsens at Caitlen Station

The fighting across Caitlen Station escalated sharply in 11.025.M42, as multiple factions continued their attempts to secure or plunder the sprawling, half-derelict installation. What had begun as scattered skirmishes had by now become a full-scale free-for-all, with every major power in the Aleph Sector committing elite teams to gain even a sliver of control.

Kasrkin Insertion Efforts Collapse

The Imperium’s most significant commitment came in the form of several Kasrkin insertion teams, dispatched by General Van Dorn in a desperate attempt to stabilise the situation. However, these elite shock troops found themselves ambushed repeatedly across the fractured decks and drifting hab-moons of Caitlen.

One team was overrun by orks, whose ferocity and sheer weight of numbers smashed the Guardsmen before they could consolidate their landing zone. Another squad was intercepted by kroot mercenaries operating under the Federal–Tau Alliance. The kroot’s ambush tactics and unmatched close-quarters lethality shredded the Kasrkin before extraction could be attempted.

The worst blow came when yet another insertion team was destroyed by the Nemesis Claws, a warband of the Night Lords active throughout the station’s darkened hulls. The traitor marines cut down the storm-troopers with clinical brutality. Their bodies were never recovered.

By the end of the month, the entire Kasrkin operation was deemed an unmitigated disaster, with near-total losses and no territorial gains. It was a catastrophic waste of Imperial special-forces assets.

Tyranids Push Back the Federacy

Elsewhere, the Tyranid infestation—long entrenched within the station’s labyrinthine structure—erupted into renewed activity. Two separate engagements saw the bioforms overwhelming Votann Hearthkyn teams of the Federacy. The Votann had made modest early gains, but the sudden counter-surge of ravenous organisms forced them back, costing them both ground and personnel.

Despite inflicting heavy casualties on the xenos creatures, the Votann position became increasingly precarious.

Chaos and Tyranids Ascendant

By the end of 11.025.M42, a grim strategic picture had emerged:

• The Tyranids controlled large sections of the industrial belts and waste caverns, with minimal expenditure.
• The forces of Chaos—primarily the Night Lords and Death Guard—held the second-largest share of the station, having achieved their gains with ruthless efficiency.
• The Tau–Federal alliance had secured a foothold, but only after paying a steep price in troops and matériel.
• The remaining factions, from the Imperium to various xenos raiding forces, had failed to secure meaningful control of any major installation.

For the Imperium in particular, the outcome was disastrous. Elite troops had been sacrificed in failed insertions, and no strategic advantage had been achieved. The month ended with Caitlen Station more contested than ever—yet increasingly dominated by those who expended the least to claim it: the Tyranids and the servants of Chaos.

Mordecai offensives bolstered by Space Wolves

After a brief lull in frontline activity across Mordecai Primaris, the Imperium resumed its advance in the latter months of 025.M42, driving deeper into the shattered expanse of the planet’s northern hive cities. The oppressive heat of the long Mordecai summer had finally begun to break, and with it came renewed pressure from Segmentum Command for General Kutuzov to maintain operational momentum.

At the forefront of this renewed offensive were the Space Wolves, unleashed by Kutuzov to fracture the Chaos defensive line and create the necessary breach for the Imperial Guard to follow. Their assault was brutal and direct, cutting into plague-choked avenues and fortified hab-blocks with characteristic ferocity.

The Imperium’s sudden resurgence forced the Thousand Sons into a reluctant intervention. The sorcerous legion had long maintained their principal citadel deep within the northern hives, and its fall would represent a catastrophic loss for the Chaos forces on Mordecai Primaris. Thus, they moved to check the Wolves’ advance.

The Thousand Sons deployed their elite Scarab Occult Terminators, phalanxes of warp-armoured warriors whose inexorable advance had crushed many previous Imperial offensives. Their arrival threatened to halt the Space Wolves’ momentum entirely. Yet this time the blow fell not upon unprepared mortal troops but upon the Vlka Fenryka themselves.

The Space Wolves absorbed the initial psychic and bolter barrage with sheer tenacity, anchoring their line around their pack leaders and countering with devastating charges. What should have been a surgical counter-attack by the Scarab Occult turned into a grinding melee that failed to deliver the decisive breakthrough the Thousand Sons required.

Realising too late that the Imperium’s encircling manoeuvres were already in motion, the Thousand Sons were faced with a dire choice: continue the attack and risk the annihilation of their elite terminator formations, or abandon the field. The Thousand Sons withdrew under a shroud of sorcerous misdirection, preserving their forces but conceding valuable ground.

By the end of late 025.M42, the Imperium had driven significantly closer to the main Thousand Sons citadel, and the Chaos line in the northern hives was beginning to bend under the weight of sustained Imperial pressure. The long campaign for Mordecai Primaris was far from over, but the tide—slowly, inexorably—was beginning to seem indicate inevitable victory for the Imperium.

Caitlen Station: Imperium fightback

+++Excerpt from the Aleph Sector Strategic Annals, Vol. MMXLII Segmentum Obscurus Archive Record: 11.025M42+++

By 11.025M42, the Imperium could no longer disregard the escalating violence consuming the labyrinthine expanse of Caitlen Station. Long neglected and strategically vital, the station’s sudden eruption into a multi-faction battleground threatened to upset the already-fragile balance of power in the Aleph Sector. Recognising the looming danger of Chaos, xenos, or renegades securing the installation, General Van Dorn authorised an emergency deployment of Imperial insertion teams.

Krieg and the Ecclesiarchy Respond

In the absence of seasoned Astartes or elite kill-teams, Van Dorn assembled a makeshift force primarily composed of Krieg Grenadier squads, bolstered by a number of Ecclesiarchy Sanctifier teams—zealous warrior-clerics whose enthusiasm far exceeded their formal military training.

The Krieg detachment, operating with characteristic precision, made planetfall across the battered docking causeways of Caitlen Station’s outer rings. Their first major contact was with a splintered band of Necron constructs, likely tomb-theta maintenance drones left active from prior incursions. The Krieg forces executed a disciplined assault, neutralising the Necrons with methodical volleys of plasma and demolition charges. With the xenos threat pacified, they established a rudimentary forward command post—one of the first stable Imperial footholds on the station in years.

The Fate of the Sanctifiers

The Sanctifiers, dispatched on a parallel route to secure an adjoining cargo vault, met a less fortunate fate. Moving without the discipline or equipment of the Death Korps, the Ecclesiarchy-led force blundered into a hunting party of Kroot operating under the wider T’au Alliance presence.

The resulting clash was short, brutal, and chaotic. The Sanctifiers’ fervour was no match for Kroot pack tactics, and contact with the team was lost less than thirty minutes after their initial engagement. None returned. Imperial analysts grimly noted that Kroot dietary practices made their ultimate fate all too clear—the Sanctifiers were presumed killed and consumed.

Tyranid Infestation Persists

Even as Imperial forces attempted to regroup, the infestation that had plagued Caitlen Station for months continued to manifest. A small but elite team of Aeldari Corsairs, seeking to retrieve artefacts from a derelict armoury node, found itself ambushed by Tyranid bioforms lurking in the ventilation stacks. Although the Eldar cut down scores of the beasts with elegant precision, the swarm’s numbers were overwhelming. Vox-intercepts recorded their final moments—psionic static, splinter fire, and shrieks of chitin.

None of the Corsairs escaped.

Thus, by late 11.025M42, Caitlen Station had become an active warzone. The Imperium had secured a foothold, yet every corridor remained contested. Tyranids, Necrons, Kroot mercenaries, Chaos warbands, and more all stalked the shattered super-structure. The station’s fate—and the strategic future of the Aleph Sector—hung precariously in the balance.

Early gains for chaos at Caitlen Station

 +++Excerpt from the Chronicle of the Caitlen Reclamation, Segmentum Obscurus Archives, 025.M42+++

In the months of 10–11.025M42, the long-dormant void-colossus of Caitlen Station once again became the stage upon which the rival powers of the Aleph Sector declared their competing ambitions. Of these, the forces of Chaos were the first to make their intentions unmistakably clear. The arrival of several small but elite warbands—primarily elements of the Night Lords and Death Guard—marked the beginning of a renewed and methodical Chaos attempt to assert dominance over the fractured installation.

Night Lords Incursions

The Night Lords, ever preferring terror over subtlety, announced their presence with a vicious strike against a T’au scouting element. A lightly armed cadre of T’au Pathfinders, attempting to map one of the station’s derelict container warrens, was ambushed and eradicated. Despite the full application of T’au ranged discipline—markerlights, pulse volleys, and supporting drones—the VIII Legion warriors pressed through the fusillade with murderous purpose. The Pathfinders were annihilated in close combat, their final transmissions little more than screams and static.

Death Guard Advances

Elsewhere, a contingent of Leagues of Votann Hearthkyn, operating under Federacy sanction, attempted to probe deeper into the station’s lower armoury tiers. They encountered entrenched Death Guard elements, whose noxious resilience and inexorable advance quickly turned the engagement into a mire of attrition. The Votann, though well-equipped and disciplined, were eventually overrun, their position choked with corrosive fumes and plague-ridden munitions.

Tyranid Predation

At roughly the same time, General Van Dorn, seeking to reassess Imperial claims to the station, dispatched a small fireteam of Krieg Guardsmen. They progressed no further than the outer vent-shafts before the resident Tyranid infestation descended upon them. The Guardsmen fought with characteristic stoicism, but were swiftly overwhelmed and consumed. Their vox-logs ended abruptly, offering one more grim reminder that the biomass corruption of Caitlen Station remained very much alive.

Dark Eldar Misfortune

A separate Drukhari raiding party—believed to be a strike cell of Kabalite agents supported by Mandrake shadow-killers—attempted to exploit the chaos and plunder an abandoned weapons store. They instead crossed paths with a Night Lords kill-clade. The VIII Legion warriors surged into melee with savage delight, cutting down the Mandrakes before their shadow-tricks could avail them. The Drukhari force was destroyed almost to the last, their souls added to the terror-legion’s grim trophies.

Harlequins and the Votann

On the far side of Caitlen Station Primary, a Hearthkyn expeditionary team stumbled into an enclave of Aeldari Harlequins. Any attempt at diplomacy proved futile; the Harlequins dismissed the Votann with uncanny laughter and drew weapons in the same gesture. What followed was a bewildering whirlwind of motion. Even the formidable firepower of Votann auto-missile arrays could not pin down the capering xenos. A single Death Jester, dancing through the storm of rockets, accounted for multiple Hearthkyn casualties before the survivors disengaged.

By the end of 11.025M42, the status of Caitlen Station had deteriorated into a shadow war of unending skirmishes. No faction held clear control; all sought advantage. Yet the sudden, coordinated aggression of Chaos warbands had made one fact clear: Caitlen Station would soon become the next major battleground of the Aleph Sector’s ever-expanding wars.

Caitlen Station erupts in violence

By the latter half of 025.M42, as the wars of the Aleph Sector ground on without decisive resolution, the attention of many competing factions once more drifted toward the colossal void installation known as Caitlen Station. Once the pride of the Imperial Navy and the lynchpin of the strategic defence grid of the Zadoc Subsector, the station had—over decades of warfare, xenos incursion, and Imperial retreat—fallen far from its former glory. What had been a monumental fortress system had degraded into a lawless sprawl of shattered infrastructure, adrift in a system marred by neglect and predation.

Caitlen Station was never a single edifice but an immense conglomeration of void-facilities:

• Titanic drydocks capable of servicing battleships and grand cruisers.

• Vast container fields holding centuries' worth of matériel, much of it lost to record.

• Forgotten weapons vaults, some dating to the Great Crusade.

• An immense starfort, still half-functional despite millennia of piecemeal repairs.

These structures were spread across drifting planetoids, orbital rings, scattered platforms, and a dense mass of debris-fields that had once formed part of a coherent defence network.

In the wake of the Imperium's loss of much of the Zadoc Subsector, Caitlen Station had been abandoned to its fate, left to decay at the edge of civilised space. In the years that followed, it became a haven for scavengers, pirate enclaves, and warbands of every persuasion. By the time Imperial tacticians once again took an interest in 025.M42, the station was a morass of infestation and internecine violence. Tyranid bioforms, spawned from drifting spores and derelict bio-ships, nested in the internal superstructure; Ork freebootas prowled the docking caverns; and innumerable smaller bands—Traitor Astartes kill-clades, human renegades, and unknown xenos—vied for whatever spoils they could carve out.

Yet even in this state of ruin, Caitlen Station remained a prize too valuable to ignore. Its weapons caches contained relics of forgotten wars. Its hulked vessels could be stripped, reconstructed, or cannibalised. Its remaining infrastructure, if secured, offered unmatched strategic advantage.

Thus, across 025.M42, the factions of the Aleph Sector dispatched small, elite infiltration teams into the labyrinthine depths of the station and its outlying facilities. Each sought a different objective:

• The Imperium, hoping to reclaim or at least deny crucial matériel.

• The T’au, seeking technology or safe harbour for future expansions.

• The Orks, eager simply for loot and a good fight.

• The Chaos warbands, drawn by both opportunity and the echoes of ancient corruption.

• Rogue Traders, pirates, and mercenary groups, each with their own ambitions.

These expeditions rarely encountered one another directly, for the station’s immensity allowed teams to vanish into the dark between bulkheads. But their actions—sabotage, scavenging, purges, and skirmishes—echoed through the station’s fractured ecosystems, creating a shifting battlefield of deception and opportunity.

Though no faction would claim full control of Caitlen Station by year’s end, the conflicts of 025.M42 ensured it remained a site of vital strategic interest—and a nexus of future confrontation. For in the Aleph Sector, ruins are never truly abandoned, and the shadows of Caitlen Station still promise wealth, power, and death in equal measure.

Chaos consolidate forces around Calliden

In the closing months of 025.M42, the forces of Chaos enacted a deliberate and coordinated withdrawal from the Hadron Expanse, consolidating their strength in the more defensible fastnesses of the Perseus Deeps. This manoeuvre, long anticipated by Imperial strategos but executed with characteristic unpredictability, marked a significant shift in the strategic balance of the region.

On Calliden, recently ravaged by conflict on multiple fronts, the Death Guard began a systematic purge of lingering Necron resistance. These automaton legions, reawakening in scattered pockets across the planetary crust, were methodically hunted down and eradicated by the Plague Marines. The Death Guard’s implacable advance left behind fields of virulent corruption, denying the Necrons any opportunity to reconstitute their forces.

Simultaneously, the Night Lords conducted a brutal counter-operation against an Aeldari strike force that had descended upon the system. The Eldar, likely attempting to sabotage the Chaos withdrawal and disrupt whatever darker schemes lay beneath it, were met with surgical and sadistic precision. The VIII Legion remnants successfully repelled the xenos intervention, preserving the wider strategic plan of the Chaos coalition.

With their route secured, the Night Lords then turned their efforts toward delaying the relentless Tyranid swarms advancing through the Rifts of Hecate. Though far from a true stand, their brutal holding actions bought precious time. Amidst this carnage, the Night Lords orchestrated their escape through an unexpected and grotesque vector: the Nurgle plague world Fecus Major.

Witnesses—few who survived with mind intact—reported that Fecus Major itself translated into the Calliden system after an arcane warp-ritual of prodigious scale. The diseased planet’s sudden appearance unleashed waves of empyric contamination and reality distortion, providing the perfect screen for the Night Lords’ withdrawal while further unbalancing the already volatile region.

By year’s end, the forces of Chaos stood entrenched across the Perseus Deeps, strengthened by their grim successes. The Hadron Expanse, meanwhile, was left in a state of catastrophic ruin, with Imperial, xenos, and Tyranid forces struggling amidst worlds made desolate by war, plague, and warp-born abominations.

The long-term consequences of this manoeuvre remain unclear—yet all Imperial tacticae agree: the Deeps grow darker still.