4: Chapter 4: Thirty Survivors in the Ruins, the Swarm Decides to Keep Them Alive

Deep within the hatchery, the Overmind was conducting its seventh round of gene recombination experiments.

The subject was an isolated Larva. Its body was anchored to the inner wall of the incubation chamber by mycelium, with nutrient solution injected directly into its body via tubes to accelerate its metabolism. The Larva's genetic sequence was laid out within the Hive Mind—every gene strand under real-time monitoring.

The pain-suppressing neural structure of the Chaos Hound had been extracted and streamlined into an independent genetic module. The core function of this module was to close specific neural signal channels when the body sustained damage, completely blocking the perception of pain while simultaneously releasing high concentrations of adrenaline-like substances to convert pain into combat euphoria.

The issue with the original version was that this neural structure would spiral out of control under the catalysis of Chaos energy, causing the host to perceive no damage at all, continuing to act until the body literally fell apart. What The Swarm needed was a controllable version—blocking pain during combat, but restoring perception after the battle to allow for precise repair of damages.

The Overmind added a switch sequence to the genetic module.

This switch was directly controlled by the Hive Mind. In a combat state, the switch would open, and pain blocking would activate; after the battle, the switch would close, damage perception would return to normal, and the Zerg unit would automatically perform tissue repair.

The first experimental Larva completed its transformation.

It emerged from its cocoon slightly smaller than a standard Zergling—a large amount of biomass had been used to construct the complex neural regulation system, leaving fewer resources for muscle and carapace. However, this new type of Zergling's nervous system was three times as complex as a normal one, with a row of glowing nodes embedded on either side of its spine—the physical carriers of the switch sequence.

The Overmind drove it to undergo testing.

The new Zergling deliberately slashed its own forelimb with a bone blade. The skin tore, and body fluids seeped out. But its movements showed no hesitation—the pain signals were completely blocked, replaced by a surge of euphoric energy into its muscles; its next leap was actually faster than before it was injured.

“Stop testing.”

The command reached the switch sequence. The glowing nodes dimmed. The new Zergling's body suddenly stiffened—pain signals returned, and damage perception reconnected. It lowered its head and began to methodically treat the wound with its saliva.

Success.

The Overmind labeled this genetic module as “Pain Switch Module-01” and encoded it into the genetic template for the next batch of Zerglings.

But this was not the most critical experiment.

On the other side of the incubation chamber, another Larva was undergoing a more dangerous modification—Chaos Adaptation.

It was injected with a trace amount of purified Chaos energy. The dosage was only one-thousandth of the concentration found in a Chaos Hound, using specific enzymes from the creep's digestive juices to neutralize the corruption effects of the Chaos energy, retaining only its catalytic acceleration of biological tissue.

The Larva's cell division rate rose exponentially after the injection. Wound healing, carapace synthesis, muscle fiber hyperplasia—all physiological activities related to growth were accelerating.

Ten seconds later, cell division began to spiral out of control.

Cysts appeared on the Larva's skin; when they burst, what flowed out was not body fluid, but a purple-black pus condensed from Chaos energy. The genetic sequence began to break and recombine, and random mutations accumulated at a rate visible to the naked eye.

The Overmind terminated the experiment.

The Larva was sent into a digestive sac by mycelium to be decomposed and recycled.

“The acceleration and corruption effects of Chaos energy are inseparable at the molecular level.”

The Overmind recorded this conclusion in the Hive Mind. At least for now, it was impossible. The nature of Chaos energy dictated that it was always accompanied by disordered mutation—if you wanted its catalytic power, you had to endure its risk of corruption. It was like using fire for warmth: you could enjoy the heat, but you couldn't complain about the smoke.

Unless—

A biological sample could be found that could survive in Chaos energy without being corrupted.

A species naturally immune to corruption, or at least capable of tolerating high concentrations of Chaos energy without losing self-awareness.

There were none on this planet.

The native species all hid deep within the crust to avoid Chaos energy. Chaos Hounds and Chaos Spawn were themselves products of corruption. Chaos Cultists were humans who actively embraced corruption.

A broader gene pool was needed.

The Overmind's consciousness turned toward the north.

The lair where the Chaos Cultists had fled.

The answer might be there.

One hundred and twenty kilometers to the north, scout Zerglings discovered a Chaos Cultist stronghold.

It wasn't a primitive cave or camp.

It was an abandoned human architectural complex.

The style of the buildings reminded the Overmind of the giant hive-like cities of the Imperium of Man known as “Hive Cities”—vertically stacked structures of steel and concrete where hundreds of millions of people were crammed into layers of residential units, forming a self-sufficient, closed ecosystem.

But this one was dead.

The shell of the Hive City had been torn open from one side by some immense force. The break showed no normal jagged marks of torn metal, but was eerily smooth—as if sliced through by an absurdly large blade. The internal layers of the Hive City were exposed like an anatomical specimen of a beehive.

Tens of thousands of corpses were sealed between collapsed concrete and twisted steel beams. Their posture was not that of people struggling to survive, but a ritualistic kneeling—everyone had knelt in the same direction before death, toward a cathedral spire split in two deep within the Hive City.

A symbol was carved into the cross-section of the spire.

A circular symbol with eight arrows radiating outward.

The Chaos Star.

The Chaos Cultists were gathered at the lowest level of the Hive City, in the catacombs beneath that torn-open fracture. The scout Zerglings' senses captured their energy fluctuations—at least two hundred Chaos Cultists, spread across a ritual site converted from underground tombs.

And something else.

The Zerglings' sense of smell picked up the scent of genetic information—not the distorted genes of Chaos corruption, but relatively complete, uncorrupted human genes.

A group of about thirty people.

Living, uncorrupted humans, locked in a secret chamber in the deepest part of the catacombs.

The Overmind's attention was piqued.

Thirty pure humans. Thirty sets of complete human genetic sequences untwisted by Chaos.

And—if any of them were what humans called “Psykers”—a complete set of psychic talent genes.

This was of immeasurable value to The Swarm.

“All scout units. Maintain stealth. Do not expose yourselves.”

Two scout Zerglings lay low on the outskirts of the catacombs, quietly sowing creep spores into the silt of the underground river. The mycelium began to grow slowly at a minimum metabolic rate, releasing no active energy fluctuations and only performing passive information gathering.

Meanwhile, the main force of The Swarm began moving north.

Twelve new Zerglings—the total output of three incubation batches—formed the vanguard.

Twenty standard Zerglings served as the support echelon.

Two newly hatched Hydralisks acted as long-range fire support.

Hydralisks were the backbone of The Swarm in the Koprulu Sector. Two sizes larger than a Zergling, their serpentine lower bodies supported an upright upper torso, with hundreds of hollow bone spines arranged along their carapace. They launched these spines at high speeds through muscle contraction, with an effective range exceeding eight hundred meters, and the tips of the spines could switch between various warheads—penetrating, explosive, or corrosive.

The spines of these two Hydralisks were coated with concentrated creep digestive fluid. They would have a special killing effect on Chaos Hounds.

This was the entirety of The Swarm's current military strength.

Before setting out, the Overmind scanned the newly unlocked genetic templates one last time.

The brain structure information extracted from human genes had brought an unexpected harvest. The working mechanism of the human prefrontal cortex—especially the functions of decision-making and impulse inhibition—caused the Overmind to re-examine its own command hierarchy design.

The Swarm's original primary command mode was the Overmind directly controlling all individuals. The advantage of this mode was absolute unity; the disadvantage was the information throughput bottleneck. When the scale of The Swarm expanded to the hundreds of millions, the Overmind would need to process the sensory inputs and behavioral outputs of billions of individuals simultaneously, causing millisecond-level delays even with its processing power.

The human solution was hierarchy.

The brain does not directly control every cell; instead, it issues commands through the nervous system step-by-step: Brain → Spinal Cord → Peripheral Nerves → Muscle Fibers. Each level has the capacity to process simple information autonomously, with only information requiring a decision being reported up to the brain.

The Overmind did not need to replicate the human nervous system—The Swarm's Hive Mind was already a more efficient neural substitute—but it could borrow the idea of hierarchy.

A new genetic template began to take shape in the design vat.

Larger than a Zergling, more agile than a Hydralisk. Possessing a more complex neural center than ordinary Zerg units, it would be capable of autonomously commanding a small combat formation for short periods when disconnected from the Overmind's direct control. It would not fear, would not think, and would only make optimal judgments at the tactical level.

The Overmind named it: Brood Queen.

But this template required too much biomass. All currently accumulated biomass would only be enough to hatch one Brood Queen. Furthermore, the Brood Queen's genetic template was not yet perfect—it needed more combat data as a basis for tuning.

Shelve it for now.

After taking the Chaos Cultist lair, absorbing the gene samples of those two hundred-plus cultists and thirty pure humans, and accumulating enough biomass, the hatching of the Brood Queen would begin.

Meanwhile, in the Warp.

A black vessel of the Imperial Inquisition was in transit.

Inquisitor Marcus Aurelian stood before the bridge's observation window, gazing at the churning Warp outside. He was fifty, but looked sixty—no one who had served in the Inquisition for twenty-five years looked younger than their actual age.

The data slate in his hand scrolled through scanned images of that planet.

Code Name: Dead Silence-42.

The Imperium had colonized this planet thirty thousand years ago, establishing that Hive City and mining underground veins. But the Chaos tides around the fall of Cadia had swept through this sector, and the planet was marked as "Lost" in the Imperial archives.

Now it had come back to life.

It wasn't the return of human residents.

Purple creep covered vast areas of the surface. Scanners captured dense life-sign readings—thousands of small organisms active within this purple ecosystem.

“It's not Tyranids,” the Tech-Priest beside him said flatly. “Tyranid creep is flesh-colored and consumes everything. This creep only covers the surface and hasn't eroded into the deep underground mineral veins. It is... farming this planet.”

“Farming?” Marcus repeated the word.

“Yes. It is building, not plundering.” The Tech-Priest pulled up a set of comparative data. “Thirty standard days ago, the creep coverage was approximately zero point three percent of the surface. Now it has expanded to two percent. If it maintains this speed, it will cover the entire planet in one hundred and twenty days.”

Marcus was silent for a moment.

“When do the Grey Knights arrive?”

“The message has been sent. The nearest strike squad is in the Warp lanes and is expected to rendezvous with this ship in ten days.”

“Ten days.” Marcus looked out the window. “A new xenos can build an empire in just one hundred and twenty days.”

He turned toward the tactical table.

“Bring up the starchart for that system. Which is the nearest Imperial Guard station?”

“The 37th Frontier Garrison Fleet. Two infantry regiments, one armored company, no Astartes.”

“Not enough.” Marcus's finger traced the system map. “Have the 37th Fleet prepare for support. Also, send a dispatch to the nearest Forge World to request the assistance of a Titan Legion.”

The Tech-Priest was stunned.

“Lord Inquisitor... a newly discovered xenos requires a Titan?”

Marcus did not answer. He stared at the scanned images on the screen, at that patch of purple creep. In the Inquisition archives, he had seen too many new xenos—most were wiped out in the first purge after discovery. But the feeling this one gave him was different.

He couldn't say why.

Perhaps it was because the speed of that creep's expansion was too regular. It wasn't the wanton spread of wild growth, but a rhythmic, directional, and strategic advancement.

As if it were deploying troops.

“Do as I say.”

“Yes.”

The ship continued its voyage through the Warp.

Planet Dead Silence-42. North.

The main force of The Swarm arrived at the outskirts of the Chaos Cultist stronghold.

The entrance to the catacombs was the ruins of a bombed-out cathedral. Half of a holy icon lay in the rubble; its face had been chipped away, and two rotting human palms were stuffed into the eye sockets.

The energy fluctuations at the ritual site began to intensify.

The Chaos Cultists were summoning something.

The Overmind's consciousness swept over the terrain, calculating for five minutes.

Then it issued the attack order.

“Kill all Chaos Cultists. Leave those thirty pure humans.”

“All units—”

“Attack.”

Twelve new Zerglings charged into the catacomb entrance simultaneously. In the darkness, the screams of Chaos Cultists and the roars of Chaos Hounds rang out at once.

The battle—

Had begun.