The Skaven did not interfere in the battle for the final Key-Fragment. Without their meddling, history repeated itself: Commander Farsight, possessed by Khornate fury, slaughtered his foes before regaining his will and retreating. Vashtorr claimed the final prize.
The Arkifane was ecstatic. Abaddon, too, was pleased. The ancient weapon of the Old Ones was finally within reach, a tool capable of toppling the Imperium.
The World of Wyrmwood.
This was Vashtorr's forge-world, a corrupted mirror of Caliban. Here, the three keys would form the Dissonance Engine to unlock the Vault of the Old Ones.
"Heh-heh... My grand ambition is at hand!" Vashtorr gloated within his mechanical foundries. "I need time, Abaddon. Help me!"
"I shall prepare the defenses," Abaddon replied, his topknot swaying as he nodded.
"Warmaster, let us fight!" the Black Legionnaires cried out.
"Yes-yes, Skaven are ready-willing to serve-obey!"
Ikit Claw, his body almost entirely replaced by cybernetic augments, bowed deeply to Abaddon with exaggerated reverence. This display incensed the other Black Legion lords; they viewed these xenos as utterly loathsome. In these upright vermin, the Astartes saw not a shred of honor or even basic integrity. These so-called Warlock Engineers were far more deranged than even the most radical tech-priests of the Dark Mechanicum. They are, after all, a foul fusion of the Black Plague and the industrial madness of a forgotten age.
Yet, Ikit Claw and his Skaven cohorts maintained a front of absolute subservience to Abaddon. Under the Warmaster's decree, they sent wave after wave of their kind to their deaths without a single squeal of complaint.
To Abaddon, these rat-men were a rare find: obedient, expendable, and effective. The current state of the Black Legion meant Abaddon acted more as a supreme warlord of a grand coalition than a traditional commander. While he held strategic authority, individual warbands often broke off to raid or pillage, ignoring specific tactical orders.
The Skaven, however, were remarkably compliant. Even after losing hundreds of thousands of their kin, they remained sycophantic. As long as they were fed scraps of Imperial and xenos technology, they functioned as the perfect meat-shields. Abaddon cared little for their motives; his eyes were fixed on the destruction of the False Emperor and the restoration of humanity's "glory" under his banner.
"Prepare your defensive perimeters," Abaddon commanded the Black Legion and the Skryre swarms. "If the lapdogs of the False Emperor arrive, annihilate them! They must not threaten my Great Work!"
"By your command, Warmaster!"
"Yes-yes, powerful-mighty manling-thing!" Ikit cackled.
The Wyrmwood system was now guarded by the Black Legion's Ebon Blade and the Skaven fleet. Ikit had personally overseen the conversion of their Ark of Omen into a Warp-Mothership, a vessel pulsating with the sickly green radiance of raw Warpstone. He christened this first flagship the World Blight.
Throughout the Wyrmwood, the Dark Mechanicum and Vashtorr's disciples deployed lures and screening forces. Originally, the Battle of Wyrmwood was meant to be a trap for the Imperium, but now Vashtorr desperately sought to keep the location hidden.
Of course, the Dark Angels should never have found Wyrmwood, but they had the "loyal and reliable" Skaven on their side.
The Skaven had "accidentally" led a contingent of Vashtorr's Dark Mechanicum into a Dark Angel ambush. Only these heretic tech-priests knew just how ruthlessly the rats would sell out an ally. Under the "Enhanced Interrogation" of the Interrogator-Chaplains, Supreme Grand Master Azrael soon learned of Vashtorr's location and the true reason for the assault on The Rock.
In a state of cold fury and righteous dread, Azrael invoked the ancient protocols. He summoned every successor Chapter of the Unforgiven, assembling a force of Legion-scale for the first time since the implementation of the Codex Astartes.
Soon, Dark Angel scouting wings slipped into the Somnium Stars and located the planet, which radiated an off-the-charts Warp signature. The intelligence was relayed to Azrael immediately. The massive fleet of The Rock transitioned from the Empyrean, bearing down on the system like an avenging hammer.
The Skaven detected them instantly. The reason was simple: when Clan Skryre had invaded The Rock, they hadn't just looted, they had infested. Within that ancient, mobile fortress, the oldest pests of humanity proved that wherever man went, the rat followed.
Even now, deep within ten-thousand-year-old machinery and shadowed alcoves, beady red eyes watched with greed, transmitting the fleet's every move back to the Skaven.
"Heh-heh-heh... they are here-coming, they are here!" Ikit Claw broke into a raspy, wicked laugh. He immediately ordered the Skaven fleet to initialize the "Betrayal-Array".
Without warning, the Skaven forces began to withdraw to the secondary lines. The World Blight and its escorts slipped into Warp-shadows to remain hidden. Ikit deliberately left the minor clans in the dark, keeping them on the front lines alongside Vashtorr and the Black Legion to maintain the illusion of a unified front, and to add fuel to the fire when the final treachery began.
Ikit offered a flimsy excuse to Abaddon, claiming their "trade-contract" was complete and they were departing. Though suspicious, the Warmaster did not stop them; the Black Legion's inner circle loathed the vermin and were glad to be rid of their stench.
Only Vashtorr, King of the Soul Forges, remained wary.
Do these vermin truly have no greed for the artifacts of the Old Ones?
He had observed their insatiable hunger for tech; small-scale skirmishes had already broken out because the Skaven kept "liberating" patents and STC fragments from the Dark Mechanicum. Yet, Vashtorr had no time to ponder. He had to synthesize the Key-fragments into the Dissonance Engine and ascend as the fifth god of Chaos.
It was then that the Warp buckled. The Dark Angel Legion-fleet burst into realspace, flooding the Wyrmwood system!