If the other regions of the Under-hive were being besieged by a desperate rabble of lesser clans, the routes leading to the Mid-spire and the opulent Upper-spire, where the defenses were far more formidable, saw the most concentrated and lethal fury of the Skaven host.
Encased in scavenged power armor reinforced by warpstone capacitors, the Stormvermin of Clan Mors and Clan Rictus advanced. Clutching their triangular Storm-shields and barking hoarse, rhythmic battle-cries, they leveled their warp-halberds. Sickly arcs of emerald lightning lashed out, striking the mutated Neophytes and Acolytes of the cult. To the uninitiated, the discharge resembled the Gauss weaponry of the Necrons, but this was pure, unadulterated warp-lightning.
"Bug-things, die! Die-die!" The Stormvermin moved with a discipline rare among their kind, locking their shields to deflect the searing las-beams and heavy stubber rounds of the Genestealer Cults. Yet, in true Skaven fashion, the elites often snarled and kicked the lesser Clanrats into the line of fire, using the bodies of their "inferiors" as living sandbags.
The Clanrats, in turn, shoved and bit at the Slave-rats, driving them forward as fodder while the Warlords watched from the rear. It was a cacophony of slaughter, screams, chittering shrieks, and vile curses. The hallmark of a Skaven offensive.
The Slave-rats broke upon the cultist lines first. Using rusted shivs, filth-encrusted claws, and jagged teeth, the sheer weight of their numbers drowned several poorly-manned hybrid outposts. Only after the vermin had paved the floor with their own dead did the Clanrats deign to step over the corpses and claim the ground. Even then, the Stormvermin were quick to beat them back into the fray, forcing them toward the next meat-grinder.
A Genestealer's monomolecular claws could easily rend the ceramite of an Adeptus Astartes, and against the lightly armored, gaunt forms of the Skaven, a single hybrid swipe was a death sentence. Yet for every rat-kin disemboweled, ten more surged forward. The Skaven displayed a madness that rivaled the cold, hive-mind driven hunger of the Tyranids, especially when the Skryre weapon teams in the rear began laughing hysterically, unleashing warp-fire that incinerated both the cultists and the Slave-rats who were too slow to flee.
The advent of Skaven-pattern power armor allowed a single rat to bear weapons that, in the "World-That-Was," required an entire team to operate. A Ratling Gunner spun his multi-barreled rotary cannon to life; with a mechanical rat-tat-tat, a storm of warp-tainted rounds shredded the Genestealer barricades in a hail of green fire.
"By the Four-Armed Emperor, we are surrounded!" a Neophyte Hybrid leader screamed, crawling toward his superior while drenched in the reeking musk and black blood of the vermin.
The three-armed cult leader's face twisted in a snarl. Hearing the ubiquitous skittering of claws and the manic chittering echoing from every ventilation shaft and shadow, he raised his bone-sword. "Order the Goliath Rockgrinders to lead the breakthrough! We fight our way back to the Spire. We regroup, we protect the Patriarch, and we exterminate these pests!"
Dozens of Goliath heavy vehicles roared to life, their massive industrial grinders capable of pulverizing the hardest ore. They formed a phalanx, their width sufficient to grind a bloody path through the furry tide. Hundreds of Atalan Jackal bikers swarmed the flanks as the cult leader gathered every remaining asset to make a desperate push for the Upper-hive transit hubs.
Invoking the name of the Four-Armed Emperor, the cultists unleashed the full power of their industrial-grade weaponry, butchering the rats in their path. At last, the massive, mountain-sized Hive Elevator came into view.
But hope died instantly. The upright-walking vermin were already crawling over every cog, strut, and cable of the structure. Warlock Engineers were directing slaves to dismantle and "refine" the massive machinery with their twisted technomancy. Human corpses were hung from the gantries as macabre banners, and Clanrats would occasionally pause to gnaw on the remains before having their snouts smashed by their overseers.
"Take the elevator or we die!" Realizing there was no other escape, the hybrid leader ordered a suicidal charge of several hundred thousand cultists against the station.
They were met by the combined might of Clan Skryre and Clan Moulder. Ikit Claw watched the approaching "bald-things" with a look of frantic, twitching ecstasy.
"YES! YES! Bring-take them down! All the bald-ones!"
Hundreds of Doom-Wheels and Doom-Flayers roared forth, wreathed in green lightning. These metal juggernauts ignored the jagged terrain, their pilots cackling as lightning cannons fired in erratic, lethal arcs. Simultaneously, Stormfiends, hulking monstrosities with Ratling cannons, warp-grinders, and wind-launchers grafted to their flesh, leaped into the fray, driven by the stinging whips of their Packmasters.
Then came the Mountain of Flesh. Dozens of Hell-Pit Abominations, the crowning masterpieces of Clan Moulder, slithered and stomped forward like a tide of gore and machinery. These heaving mounds of irregular limbs and crude mechanical implants exhaled clouds of toxic warp-gas as they crushed the cult's vanguard.
"There is no retreat! Kill!" the cult leader shrieked, looking back to see an endless sea of Skaven closing in from the rear.
"Slaughter-kill! Kill them! Hahaha, the world-star is ours!" a Skaven Warlord shrieked in delight. This was their favorite sport: the cornered prey.
In a moment, the Genestealers were buried under a tide ten times their size.
…
Lucius, draped in his black robes and clutching his shepherd's crook, walked through the sewers he had called home for a century as if taking a stroll. The rats along his path prostrated themselves, tails quivering, each desperate to catch the eye of their god, even if it meant being stepped on.
He ignored their petty vying for attention. He reached the lowest levels of the Hive, where the streets were choked with the ruins of illegal shanties and the picked-clean skeletons of the former populace. Not all humans had been eaten; the strong had been bound with reeking cords. Even the Skaven required slaves.
These captives whispered prayers in Low Gothic or spat curses at the vermin, their bodies caked in filth and rat-droppings.
"Master-Master! Oh, greedy Great Horned One... these are the gift-tributes of Clan Rictus! Presented by the humble Haulder Sneak-Blade! Yes-yes!" a massive Warlord in blood-stained power armor groveled before Lucius.
Lucius remained silent. He glanced at the hundreds of captives, then raised a hand. A terrifying surge of psychic energy erupted from his palm.
The humans began to shriek in agony. White fur sprouted from their scarred skin; their limbs elongated and snapped into new shapes; long tails burst from their spines. Within moments, they had been reshaped into tall, athletic, white-furred Skaven with massive horns—Grey Seers in the making.
The surrounding Skaven fell into a religious frenzy. To witness their god turn "hairless-things" into the most exalted caste of white-furred elites was a miracle of social mobility every brown-furred rat craved. As the billions of rats on Zavka intensified their worship, Lucius felt his power swell.
"You are my attendants now," Lucius said to the newly transformed creatures.
To the Warlord who had presented the tribute, Lucius offered a "small" blessing. He gestured to several dog-sized female rats gnawing on a nearby corpse. They began to bloat and mutate, transforming into gargantuan, mountain-sized Brood Mothers.
"They are yours, my little plaything," Lucius said coldly.
For a clan, a Brood Mother was the ultimate resource. The Warlord threw himself into the mud, squealing in gratitude for the Great Horned Rat's bounty.
With his new attendants following in a trance of awe and terror, Lucius looked toward the heights. Through his psychic senses, he felt the position of every rat on the planet.
The Upper-spire falls next, Lucius thought. A few more worlds, a few more billions of souls, and I shall truly become the Great Horned Rat.