Upon the Great Bell Throne within the Skavenblight of Zavka, Lucius watched as the Skaven fanned out in all directions like scattering vermin. To his divine senses, every Skaven soul was as conspicuous as a firefly dancing in the pitch-black of night.
Legions of rat-souls were already being stripped from the materium and funneled into the Immaterium. These souls, fueled by the collective, manic faith of the Skaven, were coalescing within the Warp to shape the horned visage of the Great Horned Rat... yet, much like the Emperor's projection in the Warp manifests as a cold, distant sun, Lucius remained anchored. So long as he did not fully ascend into the Warp or suffer death in the physical realm, he could stubbornly remain within the galaxy as a living god.
Scanning the sea of souls, Lucius noted that the densest clusters of soul-fire inevitably belonged to the massive fleets of the Great Clans.
"I may intend to become the Emperor of Rat-kind, but it seems I have no need to invent the Astartes myself," Lucius mused. After all, the Skaven bred no shortage of mad scientists.
Amidst the cacophony of a million frantic, incoherent prayers, the plea of a certain Grey Seer caught his attention.
"Great Horned Rat! Grant us the location-scent of those strongest, most-powerful gene-things! Find them for us, yes-yes!"
"Ah, so it begins. This must be a Moulder lot," Lucius said, isolating the prayer. Indeed, it originated from a splinter fleet led by none other than Throt the Unclean.
Lucius's Great Crusade was far from aimless. While the Skaven, with their low cunning, would eventually identify the galaxy's most valuable treasures, his divine intervention would save centuries of trial and error.
To Clan Skryre, Lucius had whispered secrets of the Necrons and the internal workings of the Adeptus Mechanicus. To Clan Moulder, however, he had revealed the staggering potency of the nineteen stages of Astartes gene-seed implantation, the transhuman alchemy of the Legio Custodes, and the ultimate biological apocalypse: the Tyranids.
Lucius knew that sharing such knowledge wouldn't sate Skaven greed; it would only drive them into a deeper state of mania.
In the realm of flesh-crafting, Clan Moulder had long been masters of the macabre. Even in the annals of the Old World, there were precedents like Ghoritch, a Chaos Champion whose brain was transplanted into the body of a cybernetic Rat Ogre.
Every clan venturing into the stars had its own agenda. Most sought merely to expand the swarm in hopes of catching a scrap of divine favor, or perhaps scavenging enough technology to elevate their standing.
Yet the goals of the four Great Clans were razor-sharp. The Grey Seer Clan maintained no independent fleet; their seat of power remained the Hive-city of Zavka, now rechristened Skavenblight. As the sorcerer-priests of their race, they embedded themselves within the fleets of all other clans to ensure the faith of the Great Horned Rat was upheld, and to keep a watchful eye for heresy.
Clan Eshin remained the blade in the Great Horned Rat's hand. This clan of assassins served as the equalizer for the Council of Thirteen, threatening all clans equally. No Warlord could ever be certain just how deeply the Eshin shadows had permeated his own ranks.
This left the most aggressive expansion to Clan Skryre, driven by a lust for maddening technology and "inspiration," and Clan Moulder, ever-hunting for the most horrific organisms to subject to their flesh-shaping vats.
…
Deep within the Warp-conduits, the Moulder fleet surged forward. Lord Verminkin, the ruler of Clan Moulder, had no intention of letting his clan's destiny be dictated by the treacherous "rat-engineers" of Skryre. To ensure their dominance, he had dispatched his second-in-command: Throt the Unclean.
Throt, the three-armed, perpetually famished Master Mutator, glared at the flickering monitors of the ship's bridge. He despised the Skryre technology they were forced to use.
"The Horned Rat... the Horned Rat tells us! There are hairless-things called 'Tyranids' in this galaxy! Greatest bio-meat, best-best for shaping! All of it... all the good-good meat belongs to Moulder—YES-YES!" Throt shrieked, his voice cracking with gluttonous fervor.
In the Skaven mind, all biological mastery was the birthright of Moulder. To decipher the divine will of their god, however, they were forced to rely on the Grey Seers.
Much like the Astropaths and Navigators of the Imperium, the Grey Seers served as psychic conduits and navigators, bridging the gap between the swarm and the Great Horned Rat. A Grey Seer, draped in tattered robes and clutching a Staff of Supremacy, struggled to straighten his hunched back. As a prophet of the god-on-earth, no Skaven dared challenge his authority while Lucius walked the stars.
In response to the Grey Seer's ritualistic supplication, a revelation from Lucius arrived.
The Grey Seer watched as the flesh on the back of a nearby slave-rat began to blister and warp, forming a bloody, living star-map. He nodded in ecstatic freneticism, then slammed his staff down, magically flaying the screaming slave to preserve the "parchment."
"This is the way! YES! This is the scent!" the Grey Seer shrieked.
Throt the Unclean peered at the gory map with suspicion, yet he dared not question the Great Horned Rat's design. He merely looked upon the Grey Seer with a hunger that was barely contained.
"The Horned Rat has given us the kill-path! YES!"
Under the Grey Seer's direction, the Moulder host veered sharply toward a specific coordinate in the dark reaches of the void.
…
Indeed, Lucius's primary motive for the Great Crusade, beyond mere expansion, was to test the range of his spiritual tether to the Skaven. As the soul-fires of his children drifted like sparks across the galaxy, he focused his will on the Moulder fleet, the furthest of his probes.
Knowing their expertise in genetic engineering, Lucius knew the best "sparring partners" for Moulder, aside from the Astartes, were the Tyranids, the ultimate biological weapons. He was morbidly curious: what would happen if the treachery and madness of Clan Moulder met the hyper-evolved biomass of the Hive Mind?
As for what would happen to the Moulder fleet? If they were too stupid to flee when outmatched, they didn't deserve to be called Skaven.
Simultaneously, Lucius broadcast coordinates to the other clans tailored to their specific "tastes." Clan Skryre, for instance, was being navigated toward a mid-sized Forge World of the Adeptus Mechanicus.
"Success or failure matters little," Lucius chuckled, leaning back upon his throne in the Council of Thirteen. "The reproductive rate of the rat is a force of nature."
He looked up, his gaze piercing through the spire-roof toward the stars, and the Immaterium beyond.
"There is time. Plenty of time."
Lucius was determined. In this material universe, he would break the horrific stranglehold of the Four Powers, or rather, the Five.
Why worship them when you can have the Great Horned Rat? We're much more adorable, after all.