Hive worlds exist to feed the Imperium's endless appetite for weapons and resources. They are colossal cities of steel, rising kilometres into the sky as layer upon layer of factories, hab-blocks, and manufactoria are built atop one another. Compared to the precision of Forge Worlds their craftsmanship is crude, but their output remains immense. In their wake, the planet beyond the hives has been reduced to a wasteland of poisoned skies and endless deserts of ash.

Life within a hive is short and unforgiving. Billions are crammed into decaying structures, labouring without pause for a system that offers nothing in return. Some accept this fate and abandon any hope of a better life. Others slip into the shadows, joining gangs, cults, or criminal networks, choosing danger over the certainty of servitude.

Power on Necromunda is concentrated in the hands of the Great Houses, a small number of immensely wealthy noble families who rule from the spires. Above them stands House Helmawr, the ruling House of the planet, its authority recognised by the Imperium and enforced through harsh laws, charters, and tradition. The Great Houses beneath it are investors rather than producers, dealing in contracts, influence, and leverage rather than labour.

Beneath the spires and the Great Houses stand the Clan Houses in the heart of the hive cities, each responsible for a critical part of Necromunda's industrial output. Every House has its own traditions, dialects, dress styles, and codes of behaviour. Power struggles between them are fierce and often violent, yet no House can stand alone. Each relies on the others for resources, expertise, or protection, binding them together in a web of necessity and simmering resentment.

The Houses are locked in constant rivalry, carefully maintained to serve the reigning House Helmawr. Open war in the spires would threaten production, contracts, and the tithe owed to the Imperium. As a result, conflict is pushed downwards into the Underhive, where it can be contained and exploited.

House gangs descend to claim turf, seize factories, sabotage rivals, and secure resources that can be traded for influence above, their existence and conflicts an accepted part of the system.

Not everyone fights for a House, though. The Underhive also draws the desperate and the fallen. They descend there to fight over the spoils and waste of the manufactoriums above. As long as the hives keep producing and the spires remain untouched, violence is not only tolerated, it is encouraged, for it keeps House Helmawr secure by ensuring its enemies remain divided.

Surrounding the hives stretch the Ash Wastes, vast deserts of radioactive dust, deadly fauna, and toxic storms. Though utterly inhospitable, traversing these wastes is essential to Necromunda's survival. Trade convoys travel between the hives, hauling supplies, weapons, and raw materials across the wasteland.

Control of these routes is fiercely contested. Clan Houses, Guilds, and nobles all seek to establish control over the ash roads and the sparse settlements and trading posts that cling to them. But, where trade flows, so too do criminals, outcasts, and opportunists, carving out harsh lives in the Ash Wastes.

The revolutionary spark is struck when Lord Gerontius Helmawr, long-ruling master of Necromunda, is left near-dead by an assassination attempt. Hovering on the edge of death, his body is sealed in a stasis-casket. His administration is thrown into turmoil, with his daughter, Lady Haera, outmanoeuvring her siblings and stepping forward to rule in his name.

House Helmawr's grip begins to slip as unrest spreads through the hives. Old grudges resurface, supply lines are sabotaged, and violence erupts across the planet. Amid the chaos, Lady Credo steps into the open as a rival power, presenting herself as a liberator and heralding the coming of an unnamed leader. What might once have been settled through inheritance or intrigue now becomes something far harsher. The Succession is no longer about lineage - it is about the survival of House Helmawr.

The power vacuum left in Helmawr's wake tears Necromunda apart. Lady Haera, now the de facto ruler, finds herself hunted from all sides. She has already eliminated as many rivals as she can, including her own siblings, yet even that bloodshed proves insufficient to secure her rule.

Open war erupts in Hive Primus. The Noble Houses turn on one another, casting off their long-held allegiance to House Helmawr. With enemies closing in, Lady Haera is forced to flee the hive, heading for the Dust Wall and the protection of the Enforcers still loyal to her house around Hive Secundus. Her escape is cut short when her airship is brought down, forcing her to cross the Ash Wastes on foot and seek refuge.

Across the wastelands, Ash Waste Nomads led by the Lady of Ash move towards Squat-held territory and the entrances to the subterranean tunnel networks. Lady Haera finds shelter amongst the Squats and slips into the depths of the underway.

Meanwhile, the forces loyal to Ozostium and his Prophet tighten their grip on the Palatine Hive cluster. The old order has fallen, and in its place rises something far older and far more ominous.

Ozostium Aranthus claimed the throne of Necromunda, restored through faith, martial force, and legend. Yet the civil war didn't end.

Lady Haera, once more allied with Tamino, prepares for a final strike. The Sthenian-pattern Spyrer suit offers a weapon capable of ending even an undying Aranthian lord.

With word spreading of Lord Gerontius Helmawr's survival, loyal gangs and Spyrers rally to House Helmawr for one last gamble. They fight their way up through Hive Primus, determined to reclaim the spire in his name.

They face renegade Enforcers, rival gangs, and the full weight of Ozostium's followers. At the very peak of Hive Primus, within the Imperial Spire itself, Ozostium awaits them. The Aranthian Succession will not end with a coronation, but with a bloody reckoning.