Roger Castor stood in the main control room of the fission power plant, staring blankly at a reactor fuel rod that showed a steady reading.
The surroundings hummed with the drone of transformers, and the air carried the sharp tang of ozone. The radiation levels here actually far exceeded safety limits; a normal human standing here for ten minutes would begin to lose their hair.
But Roger didn't care. After all, he had no hair left to lose.
Most of his head had been replaced with a cold metal shell, with only a small patch of skin and flesh still clinging to his jawline.
Roger held a tube of nutrient paste that had been squeezed dry. He pressed his hydraulic-assisted finger against the tube with all his might, managed only to extract a single drop of green, snot-like gelatinous substance.
Roger sighed and smeared the drop into his mouth. It tasted terrible—like moldy machine oil. But it was his only meal in the past twenty-four hours.
He was the leader of the Brotherhood of Rust, the spiritual pillar and technical core of this settlement, but right now, he was truly starving. In the Underhive of this industrial world, a Tech-Priest starving to death sounded like a joke, but it was a harsh reality.
The Brotherhood of Rust wasn't a violent gang, nor was it some fanatical cult. They were a group of "Technical Heretics."
In the eyes of the Imperial Truth, that term carried a death sentence. But in Roger's view, it simply meant their minds were a bit clearer than everyone else's. Most members were like him—people who couldn't stand the Adeptus Mechanicus's idiotic rules, where "reciting prayers for three days just to tighten a screw" was the norm, or those branded as "profaners of the machine spirit" for making unauthorized modifications.
They gathered in this abandoned fission plant, relying on Roger's skills—which were just barely enough to keep the reactor running—to light a small corner of the dark Underhive.
Although the core of this old fission pile was unstable and the cooling pool was leaking, requiring daily crews to clear out the growing radiation fungi, it still worked. As long as you fed it fuel rods, it would steadily spit out millions of kilowatt-hours of electricity.
This power was enough to light ten surrounding blocks, drive a few lathes salvaged from trash heaps, and even provide enough juice for the youngsters who liked to watch holographic films.
But you couldn't eat electricity. While current could recharge their prosthetic limbs, it couldn't fill the stomachs of the half-meat bodies they had left.
Roger turned to look at the large screen in the control room. It displayed a resource distribution map of the surrounding area; most regions were gray, marked as "depleted."
Over the past month, things had become dire. The surrounding fungal harvest points had all dried up. The cultivation vats they had developed to grow edible fungi had, for some reason, suddenly become overrun with toxic black mold. Even the mutant rats that usually scurried everywhere had become scarce.
This abnormal ecological collapse filled Roger with deep unease. After surviving in the Underhive for so many years, he knew this usually meant something more terrifying at the top of the food chain was intercepting the resources.
"Boss, any word from the scouts?"
A fellow semi-mechanized subordinate walked in, holding a freshly polished wrench. This was Ben—owner of a rare single-syllable ID. Originally a ventilation technician, he was sentenced to flogging by the Mechanicus for installing an unauthorized filter in a pipe, after which he fled with Roger.
Roger shook his head, his red cybernetic eye flickering once. "Nothing."
Ben's face grew even grimmer, despite most of it being skin grafts. "It's been three days," Ben whispered. "That was our most elite squad."
Roger didn't speak, simply crushing the empty nutrient tube in his hand.
Three days ago, he had sent a twelve-man team led by his lieutenant to an abandoned mining area four hundred kilometers away. He had found a vague record in a pile of old-world archives that suggested an underground ecological park left over from thousands of years ago. Despite its age, design standards of that era usually included self-sustaining systems. Even if only one percent of its capacity remained, it would be a literal lifesaver for the Brotherhood of Rust.
Roger had even let them take the only functional all-terrain scout vehicle and issued their last two bolters. By all rights, even if they encountered a Skinner gang, they should have been able to fight their way back.
But now, there was only the crackle of static on the radio. That deathly silence made Roger's heart sink bit by bit. It seemed the underground park was indeed a death trap. Previous explorations had ended the same way—no matter how many were sent, only screams or total silence returned.
Some said it was haunted by Chaos daemons; others said it was a Genestealer nest. Roger didn't know the truth; he only knew his brothers weren't coming back.
This powerlessness filled him with rage. He was enraged by the absurdity of this world. The nobles and lords above lived in spires in the clouds, possessing the best resources and eating untainted synthetic meat, yet they spent their days in political infighting and collecting "antiques."
They would rather spend billions of tons of resources building a symbolic temple than bestow a shred of technology to the Underhive—they wouldn't even release the blueprints for a basic water purifier.
In the eyes of those high-ranking figures, people like Roger were heretics to be purged. Yet the irony was that these "heretics" were the ones trying to use their "forbidden" skills to survive in this hell.
"Tell the brothers to get ready," Roger said suddenly, his voice raspy.
"Ready for what, Boss?" Ben looked up.
"Ready to catch cockroaches," Roger pointed to the vent beneath his feet. "And harvest the moss growing by the radiation pool. It causes diarrhea, but it's better than starving. If it really comes down to it..." Roger's gaze turned fierce, "we'll raid a Mid-spire supply convoy."
Ben gasped. Raiding a Mechanicus convoy was a death sentence; the Skitarii's arc rifles could cook a man instantly. But seeing the look in Roger's eyes, Ben knew they were out of options.
Just then, the red alarm light on the console flared to life.
Wail—Wail—
Hearing the emergency signal from the outer outpost, Roger lunged at the comms station and grabbed the headset. "This is the control room! What's happening? Is it the Skitarii?"
If it was the Skitarii, their only choice was to blow the reactor and take everyone with them.
The voice of the sentry came through the headset, trembling—not with fear, but with... confusion.
"No... not the Skitarii. It's a vehicle. A big one. And... and it doesn't seem to be carrying any cult markings."
Roger frowned. No markings? In this sector, who dared to drive a vehicle without markings?
"Skinners?" Roger asked, his hand already reaching for the modified melta gun at his waist. If it were Skinners coming for their power, it would be easy—just flip the high-voltage grid and fry the lunatics.
"Doesn't look like it either..." The sentry's voice was filled with bewilderment. "The vehicle is bare. Not a single spike. It looks... incredibly clean."
Clean? That word was a joke in the Underhive. Was there anything in the Underhive that could be called clean? He had lived here for years; how could he have never seen such a thing?
Without another word, Roger charged out of the control room. "Everyone, grab your weapons! To the walls!"
He roared, leading Ben toward the defensive perimeter of the power plant. The so-called defensive walls were actually just stacks of abandoned shipping containers welded with steel plates. Dozens of sallow, emaciated Brotherhood members gripped their cobbled-together firearms, peeking nervously over the wall.
Roger raised his binoculars. In the distance, on the wasteland highway littered with rubble and trash, a dragon of yellow dust rose. A half-track truck was approaching at high speed.
Just as the sentry said, the vehicle was remarkably clean. No hanging human skins, no nonsensical banners, and none of the cumbersome decorations usually added for "Machine Spirit worship." It was a pure industrial vehicle designed for transport.
That minimalist style left Roger, a tech-obsessed man, momentarily stunned. He had to admit, the modifications were beautiful. The air intake was raised high to prevent sand ingestion; the suspension was clearly reinforced, maintaining a steady posture; even the simple exhaust pipe sounded perfectly tuned. It looked like the work of a master.
But then, Roger's attention was drawn to the cargo bed. Because what was inside was simply too conspicuous.
A mountain of snow-white, unknown objects. In the dim light of the Underhive, that whiteness was almost blinding.
Roger adjusted his binoculars to maximum magnification and realized the objects were round spheres. Despite being hundreds of meters away and wearing a thick dust mask, Roger's modified olfactory sensors seemed to produce a hallucination.
He smelled a scent that had only ever appeared in his dreams.
The scent of carbohydrates.
It was the aroma released by starch when heated to high temperatures—a fragrance that could drive any carbon-based lifeform mad. A growl erupted from Roger's throat.
Ben, beside him, was also swallowing hard. "Boss..." Ben's voice shook. "That truck... it couldn't be full of food, could it?"
Roger didn't say a word. He watched as the truck didn't slow down but headed straight for the power plant gates. However, two hundred meters from the gate, the vehicle stopped.
A tall figure jumped down from the driver's cabin. The figure was encased in cold, hard engineering armor, the sunlight reflecting off the polished metal shell with a chilling glint. The man held a twin-linked heavy stubber as if it were a toy.
Then, the figure did something that made Roger's heart stop.
He turned and grabbed a basketball-sized white sphere from the cargo bed, then swung his arm wide.
Whoosh—
With the sound of rushing air, the white sphere traced a parabola through the sky. It slammed accurately onto the empty ground in front of the defensive wall.
Splat.
The sphere cracked open, revealing a pure white, delicate interior.
At that moment, the sound of everyone on the wall swallowing their spit merged into one.