"So, that is Titus... Heh. A strange sensation, truly."
In the swirling tides of the Warp, Lucius watched the unfolding catastrophe with only a passing interest. He knew that in the grand tapestry of the Five Hundred Worlds of Ultramar, the presence of a figure as storied as Titus meant the conclusion was preordained: no matter the cost, the Imperium would prevail. It reminded him vividly of his previous life, hunched over a screen playing Space Marine.
Below, Titus led an Astartes boarding party in a daring teleportation strike onto a Necron Scythe-class cruiser.
Bolstered by a protagonist's uncanny fortune, Titus carved a bloody path through the xenos interior, eventually sabotaging the local resurrection crypts used by Ammentar. The Destroyer Lord, denied his immediate immortality, was forced into a tactical withdrawal. In his wake, the Skaven of Clan Moulder remained behind, unwitting magnets for the Imperial counter-attack.
Titus felt no doubt, only the iron certainty of his duty. His chainsword whirred, dismembering vermin after vermin. When Rat Ogres lunged, he evaded with practiced fluidity, executing them with the brutal, cinematic grace of a master of the blade.
Even from his throne in the Warp, Lucius couldn't help but admire the sheer spectacle of the executions.
"I have truly become the villain," Lucius mused. Yet, he knew this was but a single branch of Clan Moulder, and Ammentar had only retreated to regroup; the C'tan Shard of the Nightbringer remained uncommitted. This was merely the opening movement of a much darker symphony.
His gaze shifted across the galaxy, following the ley lines of the Imperium toward Holy Terra. Beneath the Cradle of Humanity, the Clan Verminus was taking shape under the claw of Whitesick, the self-proclaimed Supreme Claw-Marshal.
Whitesick, a native "Teran," possessed an intimate knowledge of the throneworld's labyrinthine depths. Under his call, the common vermin of the hive-crust began to turn their chattering worship toward the Great Horned Rat.
As their malevolent will reached the Realm of Ruin, the dark echoes of the Warp responded, gifting these pests with sinewy, mutated bodies and a cruel, cunning intellect. Because of Lucius's wager with the Emperor, the Holy Light of the Golden Throne could not touch these Skaven; their gathering was unhindered. Soon, the primary warren of Clan Verminus was established beneath the roots of the Ural Mountains.
Naturally, Holy Terra was far from a utopia of safety. Even the Throne World was riddled with Chaos cults, gene-stealer infestations, and heretical spies. The occasional disappearance of a few million hive-dwellers was a statistical insignificance.
"However, a single clan cannot uphold the Skaven Empire across the other half of the galaxy," Lucius muttered, looking down at his pale, skeletal claws, the nails etched with glowing green runes.
Though his power now rivaled that of the Ruinous Powers, the various aspects of Skaven faith were already being claimed by extant clans. He had no desire to merely clone Clan Skryre within the Sanctum Imperialis; that would only lead to an inevitable and tedious civil war.
Just then, a ripple of emotion, vile, petty, and perfectly aligned with his divine portfolio, drifted into the Realm of Ruin. Lucius turned his gaze toward a world known as Ornsworld.
Even a die-hard Warhammer fan couldn't know every obscure rock in the galaxy. But as a Chaos God, Lucius merely squinted, and the entire history of Ornsworld since its inception flooded his mind.
The Realm of Ruin erupted with the Great Horned Rat's rasping, piercing laughter. The lesser rats scurried into the deepest shadows, trembling lest they become the playthings of their fickle deity.
Lucius didn't care. He laughed at his own lapse in memory.
In the lore of Warhammer 40,000, there existed a sanctioned abhuman strain known as Ratling. While their archetype was that of the halfling or hobbit, Games Workshop had seen fit to imbue them with such a profound propensity for theft and deviousness that they were practically Skaven in spirit.
Lucius stood. Since his victory over the Emperor, he had been like a sedentary gamer lost in a marathon of Total War or Civilization VI. Now, he rose to act.
He realized he had grown even more monumental. Where before he had stood like the highest peak overlooking his domain, he now felt as though he had become the firmament itself.
"This is the first time I shall move against a world of the Materium in its entirety... A modest trial of my strength," Lucius whispered, striding out of the Realm of Ruin.
The Warp, a realm of ultimate peril for mortals and daemons alike, was but a garden path for him. He intended to reach the sub-dimensional shadow of Ornsworld, churn the local tides to sever its connection to the Imperium, and then, just as the other Gods did, corrupt the Ratlings utterly.
Any vessel unfortunate enough to be in his path bore witness to the manifestation of a primordial power. One particularly luckless fleet collided with his wake like plankton hitting a leviathan.
"What is that?!"
A fleet belonging to a Night Lords warband known as the Gore-Slicked Talons was navigating the Empyrean when their stable lane suddenly transformed into a roiling tsunami of filth.
"A Warp storm? Why did the Navigators not foresee this?" the Pirate Lord of the warband roared. The Night Lords were perennially undersupplied; a storm of this magnitude promised crippling losses, if not total annihilation. The "bat-boys" began to wail, held in check only by their Lord's established reign of terror.
Then, the lead Navigator shrieked, a sound of pure, unadulterated horror. "No... no, no! It is impossible!"
"Report!!" the Pirate Lord screamed, turning his gaze to the viewscreen.
Beyond the hull lay a churning sea of madness, but the entity stirring the storm was now visible. It was a colossal, skeletal rat-head crowned with thirteen pairs of horns. Its vast, grey-white fur, each strand pulsing with baleful green light, was larger than their largest capital ship.
Confronted by such a titanic entity, even the sons of Curze, men who used fear as a whetstone, felt an inescapable, crushing dread.
The Warband Leader, Theos, summoned his last shred of courage and bellowed into the void: "WHAT ARE YOU?!"
The voice from the flea-sized ship was swallowed by the Warp-waves, but scale meant nothing to Lucius. He heard the call clearly.
He looked down at the pathetic vessel, his eyes boring into the Night Lords within.
"I AM THE GREAT HORNED RAT."
"Lies! There is no such god in the Pantheon! Your faith is written nowhere!" the Pirate Lord shouted, desperate to cling to the logic of the Warp he knew.
At that moment, the sound of scritch-scratch-gnaw erupted from every dark corner of his ship. Cables were severed by unseen teeth; nutrient pastes were devoured by a thousand mouths. Even within the Night Lords' power armor, something began to stir.
"Even the most shadows-bound killer cannot see into every corner," the entity chuckled, a sound like grinding stones. "But I shall be merciful. I shall let you see everything."
The Great Horned Rat raised a claw. An irresistible Warp-gale swept over the Night Lords' fleet, snatching them from the path and hurling them toward the Realm of Ruin to serve as fresh playthings.
Disregarding the trifle, Lucius arrived at the sub-dimensional projection of Ornsworld. His mere presence turned the local Warp-routes into a tangled mess of madness, scattering any incoming or outgoing Imperial fleets into the trackless void.