Logistics come before the army.
This holds true even for the Imperium of Mankind. Although in most heroic legends, the role of logistics is often overshadowed by great warriors and tacticians, in reality, they are the key to victory. Astartes can go long periods without food, but they need ammunition. The true backbone of the Imperium, the Astra Militarum, consists of ordinary humans who require vast amounts of supplies. Every battle is not just a contest of combat power, but a brutal struggle of logistical coordination.
Yuki understood this well, though it only applied to humans. For the Tyranids, the best logistics were the ones prepared by the enemy.
A supply fleet consisting of hundreds of massive transport vessels carried an astronomical amount of ammunition, food, and replacement troops. Some were to fill the naval deficits, some to deliver mortal thralls to the Space Marine Chapters, and a significant portion was destined for other sectors as Tithe—since the local forces were occupied with the Necrons, other sectors needed to "borrow" a bit of protection.
And this was Yuki's target.
He watched as his warships suddenly materialized before the transport fleet. The small escort fleet defending them fired back frantically, but they were utterly powerless to halt the swarm's advance. The Shadow in the Warp, combined with the Necron pylons, suppressed all psychic communication; these transports couldn't even send out a plea for help.
It was a rare sight for Yuki to see the Bio-Mother-Ships committed to combat. These theoretically massive organisms were equipped with biological macro-cannons and living void shields. They even possessed melee armaments—though, granted, Imperial Navy ships were also equipped with rams.
"This is completely like a medieval naval battle," Yuki remarked, watching tentacles tens of kilometers long erupt from the bio-ships to snag the transports, dragging them into the maws of the living vessels.
The various Tyranid strains waiting within would unhesitatingly slaughter the occupants and ferry the organic matter to digestion pools. Similar scenes played out across other transport fleets. While the Imperium's attention was fixed entirely on the World Engine, Yuki struck swiftly, devouring over a hundred transport ships.
One hundred Terran hours later, the small organisms left in the safe zone to monitor the World Engine sent back a report: the shield of the massive Necron construct had been breached. The Imperium was launching its final assault. Yuki had to move fast.
"Time to bail!"
Yuki commanded all ships to cluster together. He could see continuous explosions erupting from the World Engine in the distance. Such explosions wouldn't completely destroy the World Engine, of course; Yuki knew without thinking that a horde of "little red-robed men" (Tech-Priests) would be arriving shortly to scavenge.
"Retreat!"
The Narvhal ships appeared once more, and the Aether Fleet constructed a new Hive corridor, preparing to depart. Yuno brought out a large stash of canned Grox meat. Yuki had long heard of this famous Warhammer delicacy, but seeing the grubs squirming on the plate still made him feel a bit nauseous.
Yuno, however, didn't care at all and started eating.
"I say... isn't it dangerous to eat raw Grox?"
Yuno looked up at Yuki while chewing, as if he had just told a joke that wasn't particularly funny. "Guess what I am?"
Yuki gave a strained laugh. Telling the Great Devourer that Grox was inedible was indeed a bit too humorous.
"Just a simple joke, don't mind me."
Yuno continued eating, not forgetting to sandwich the meat between two slices of bread. "Next, we head for the Five Hundred Worlds... wait, our wormhole is being invaded?"
"What do you mean? The wormhole corridor can be invaded?" Yuki didn't understand what Yuno was saying, but Yuno's face had turned extremely grim.
She immediately seized command of the Aether Fleet, gathering all ships together. Then, through their shared vision, Yuki noticed the guest who had abruptly interrupted their journey.
It was a giant warship only slightly smaller than the World Engine. Yuki's expression twisted. He knew exactly what this was. Planet-sized constructs were rare in the Warhammer universe, and this "Great Tomb" already declared its ownership.
The Necron Super-Battleship, Song of Oblivion.
This was the flagship of the Phaeron of the Szarekhan Dynasty, Member of the Triarch, Supreme Ruler of the Necron Empire, Shatterer of the C'tan, Vanquisher of the Old Ones, The Unifier, Last of the Silent Kings, and Master of the Scepter of Eternal Glory. These were but a fraction of the many titles Szarekh had earned over the long eons.
"Yuno, I recall you and the Silent King have some history."
"Dammit, to run into this guy of all people. Can we fight, Yuki?"
"Don't be ridiculous. The Song of Oblivion carries the most elite legions of the Szarekhan Dynasty and a massive contingent of the Triarch Praetorians. This isn't something we can handle." Yuki said, "He'd better be here to reclaim the World Engine and not specifically to intercept us."
The Necrons seemed to have no intention of communicating with Yuki, firing directly upon the Aether Fleet.
"Yuno, can we get out of here?"
"I'm trying." Yuno did not fear Szarekh himself, but the Aether Fleet did. The various Tyranid fleets were relatively independent; it was impossible to summon another one in time.
"Discard a portion of them. I'll rig them up with a self-destruct function." Yuki thought it over; there really was no better way.
Dammit. Failed before the mission even began. Szarekh, I'm going to remember this. One day, I'll give you a little surprise.
Over a dozen bio-ships broke formation, while the remaining vessels provided as much cover as possible for the "seed ships" to enter the Warp. It had to be said that the speed at which Tyranids entered FTL was still impressive.
...
"Strange."
Hapshatra the Radiant spoke. He stood at the side of the Silent King's throne, speaking not for himself, but to convey the will of the Eternal King. "Why would such base creatures exhibit such behavior? Could it be fear of the great Silent King's name?"
Several Necron Overlords and Triarch Praetorian commanders stood in attendance below.
"No matter. It is of no consequence even if we let such weak enemies pass. We must hasten to other parts of the galaxy to convey the will of the great Szarekh to the dynasties that have yet to awaken."
The Silent King said nothing—hence his title. The Necron Empire had much to do: consolidation, restoration, and combating xenos threats. Szarekh had to shoulder his responsibilities once more.
He opened a star map, and the destination was revealed to everyone. It was a dynasty that could potentially threaten Szarekh's rule. The awakening of the Sautekh Dynasty had already challenged the Silent King's authority; this one must not be allowed to awaken.
"The Great Silent King shall exile this danger for the sake of the Empire. When we awaken fully, these sacrifices shall become glory."