Craftworld Yela'nk is one of the extant mobile homes of the Aeldari.
The Overmind's encounter with them was purely accidental. Nydra had provided the coordinates for a Webway gate within Commorragh; after a group of "White Aeldari" (Asuryani) used the gate, the Swarm obtained the coordinates and sent Changelings to infiltrate and scout the area.
Although the Dark and Craftworld Aeldari appeared to be at odds on the surface, they merely despised one another's lifestyles; there was no irreconcilable blood feud. In fact, trading and cooperation between Commorragh and the Craftworlds were quite common.
Due to a perceived lack of military strength, the Overmind had initially held off on attacking this Craftworld. Now, however, the time was ripe.
What the Overmind hadn't expected was that he had arrived quite late to the party. The Asuryani had traveled to Commorragh specifically to seek reinforcements. And the reason they needed help was...
Tyranids
"Seventh Frigate Formation has sustained heavy damage and is RTB!"
"Fifth Frigate Formation has neutralized the target bio-ship and is moving to support allies."
"First Destroyer Squadron has covered the Hammer of Vaul's charge to the Hive Ship. Preparing to board; target is the Tyranid Hive Queen!"
Craftworld Yela'nk was a massive, silver-blue vessel. Its size was beyond imagination, conservatively estimated at seven hundred kilometers in length. Even a cruiser looked like a tiny insect beside it. Yet, Yela'nk was actually on the smaller side; Craftworld Alaitoc was 1,050 km long, and Ulthwé reached a staggering 2,000 km. These variations existed because each Craftworld was constructed to different scales.
They housed the last remnants of the Aeldari race. Each Craftworld was a city-vessel, carrying the hopes of their people across the galaxy. Unfortunately, they lacked the instantaneous warp-jump technology of the Spear of Adun, forced instead to navigate through rare, massive Webway routes.
The Aeldari fleet was numerous, but the enemy they faced—the Tyranids—boasted an equally vast swarm of ships. The central Hive Ship was titanically large, though still much smaller than the Craftworld, measuring roughly a hundred kilometers. Compared to these behemoths, a standard Leviathan bio-ship looked pathetically small; even a Behemoth-class ship couldn't compare.
The battle had raged for some time. The Aeldari fleet was successfully frustrating the Tyranids' attempts to land on the Craftworld, while simultaneously launching a decapitation strike team into the Hive Ship to assassinate the Norn Queen.
With the resolve of martyrs, the strike team breached the Tyranid Hive Ship.
Commanding the defense was Melina, a Farseer of Yela'nk who had lived for over ten thousand years. She surveyed the battlefield calmly and murmured, "If only our kin in Commorragh would provide aid, perhaps we could end this sooner."
"Do not count on them, my Lady. They are cowards. The light of Asuryan will shine upon us; we shall prevail."
"I hope so."
Melina returned her gaze to the tactical holomap. In terms of fleet strength, the Aeldari were at a distinct disadvantage. Whether in frigates or cruisers, they could not match the scale of the Tyranid Swarm. Their only hope lay in killing the Norn Queen; otherwise, once the Tyranid ground forces reached the Craftworld, the fall of Yela'nk would only be a matter of time.
However, bad news arrived swiftly. Inside the Hive Ship, the strike team encountered the strongest Tyranid ground unit they had ever seen: a Norn Emissary. This massive creature stood over twenty meters tall; Tyranid Warriors scurried about its feet like ants.
Its titanic frame was its most lethal weapon. Massive, jagged claws easily skewered a Wraithlord—the Strike Team's primary heavy construct. The Wraithlord, normally a towering figure of strength, looked like a child's doll before the Norn Emissary.
Only the larger Wraithknights could hope to contend with it, and even then, only for a brief moment. Within a minute, the Norn Emissary took a slash to its back as the price for tackling the Wraithknight to the ground and crushing its Spirit Stone beneath its heel.
To destroy a Norn Emissary, anything short of a Titan-class unit was almost insufficient. Even as multiple "Vaul's Wrath" support batteries poured fire into it—strikes capable of melting through tank hulls—the lance beams seemed to only singe the Emissary's hide.
Meanwhile, the rest of the Aeldari forces were overwhelmed by an endless tide of smaller organisms. A boarding action was not a defensive siege; they couldn't bring their largest, most cumbersome equipment.
This signaled the failure of the decapitation strike. To make matters worse, a second Norn Emissary appeared in the corridor behind them. Yes, Norn Emissaries were mass-producible.
Some time later, Melina received a report from the Hammer of Vaul.
"Farseer, we have failed."
Melina seemed to have expected this. She sighed with resignation. Psykers of her level could glimpse the future; she had already seen the fall of Craftworld Yela'nk in her visions.
"Evacuate as many as we can. Open the Webway gates to Commorragh and the other Craftworlds. Let the civilians and children flee first. The rest of us... prepare yourselves for your souls to join the Infinity Circuit."
This wasn't Melina's first encounter with the Tyranids. Years ago, she had watched an entire Craftworld be consumed. This time, she refused to run.
"Farseer! The Swarm has breached the interior of the Craftworld!" "What? So soon?!" "But... they look different from the ones outside. I'm not sure if they are Tyranids. They appeared from the warehouses in the Third Dome District, but no Tyranid bio-ships have landed there, and the dome hasn't been breached. Lord Loken is investigating how they arrived."
"Tell Loken to be careful." "Understood!"
Meanwhile, in the Third Dome District, a Warp Spider Exarch was blinking rapidly across the rooftops. Below, Hydralisks in the street spotted him and opened fire. Loken blinked to dodge the attack and reappeared behind a Hydralisk. He raised his twin Death Spinners, firing monofilament wire that easily sliced the creature into several pieces. Before a group of Zerglings could pounce, he blinked away to safety.
"They look like Tyranids, but they are not Tyranids."
Loken was certain. When Tyranids approached him, his psychic powers would suffer from the "Shadow in the Warp," causing agonizing headaches. But before these new enemies, his psychic senses were unhindered; they were even providing him with clear warnings of incoming attacks. This proved they were not the Tyranids he knew.
Loken looked toward the direction the Swarm was emerging from and frowned.
"That's... the Webway gate? Is it another Craftworld? Or is this the work of our fallen kin in Commorragh?"