Chapter 4

The Medical District of Undertown occupied one of the better-maintained sections near the central pillars, where the Oracle’s official infrastructure ensured reliable power and cleaner air filtration. Unlike the ramshackle buildings of the Grime Pit, the medical facilities were constructed from uniform prefabricated modules, their sterile white surfaces a stark contrast to the grime-stained walls that characterized most of the Substructure.

The next morning, Raelin’s grip on Kiri’s hand tightened as they approached the clinic entrance. Her palm was damp with sweat, and he could feel the subtle tremor in her fingers which had been getting worse over the past weeks. Overhead lights hummed with steady power, casting everything in harsh, clinical brightness. Kiri squinted, raising her hand to shield her eyes.

“Too bright,” she muttered.

An Eye mounted above the entrance tracked their approach, its teal glow pulsing gently as it recorded their arrival.

“Appointment confirmed for Kiri Kestrel,” announced a synthetic voice as they passed beneath the scanner. “Proceed to Reception Area Three.”

The waiting room stretched before them in neat, orderly rows. A scavenger with a bandaged head sat in the corner, talking loudly to anyone who would listen.

“Kozar’s boys claimed the whole industrial sector,” he was saying. “Told me to clear out or they’d make sure I could never scavenge again.”

Raelin guided Kiri to seats near the back wall, away from the complainer, where she could lean against something solid. She sank into the chair with a barely audible sigh, her shoulders sagging. Raelin breathed deeply, welcoming the antiseptic scent of medical-grade purifiers after the metallic tang that permeated most of the Substructure.

“Nervous?” Raelin asked, though he could already see the answer written in the tight lines around her eyes.

Kiri’s lower lip trembled. “What if it’s something really bad? What if…”

“Hey.” Raelin’s hand found her shoulder, squeezing gently. “Whatever it is, we’ll figure it out. That’s what we do, right?”

She managed a weak smile, but her gaze drifted away from his face, scanning the other patients. Most were elderly or visibly injured workers, their worn faces murals of the Substructure itself. The same cracks, the same grime, the same stubborn endurance. Kiri sank deeper into her chair.

Then she went rigid.

Three rows ahead, a man sat with his left arm gleaming under the sterile lights. The cybernetic limb was sleek and angular, its synthetic muscle fibers visible beneath transparent panels. Neural interface ports dotted his temple, pulsing with soft blue light. A plasma rifle rested against his chair.

Kiri’s mouth fell open. “Is that…?”

“Robot hunter,” Raelin muttered, following her gaze. His shoulders tensed at the sight of the weapon.

Kiri’s eyes widened, her breath hitching as she leaned forward slightly. Raelin recognized that look immediately, the same one she wore when pulling apart rusted tech scraps under their bunk’s flickering lights, fingers tracing circuits and wires like she’d found buried treasure. Even as fatigue shadowed her face, something sparked in her gaze, drawing her forward. She unconsciously touched her own wrist, tracing imagined lines of circuits beneath the skin.

Raelin had spent hours lost in their father’s old books, but Kiri’s fascination had always been with the intersection of humans and technology, spending entire nights hunched over broken modules scavenged from the tunnels. Her illness had halted those midnight experiments, but not her imagination.

The hunter seemed to notice their attention and turned around, offering a friendly nod. He was younger than Raelin had expected, with alert green eyes and the easy confidence of someone who’d made peace with bad odds.

“First time seeing an arm like this in the wild?” the man asked with a grin, holding up his cybernetic limb and giving his fingers a quick, exaggerated wiggle. The servos made a soft whirring sound, like a cat stretching after a nap. “She’s a beauty, huh? Just don’t try arm wrestling me, I’d hate to embarrass anyone before their checkup.”

Kiri’s eyes widened, all trace of her earlier anxiety vanishing. “Is that a Series Nine joint assembly?” she squeaked, leaning forward in her seat. “The articulation range must be incredible.”

The man’s eyebrows shot up. “Now that’s not something I hear every day from…” He paused, taking in her slight frame and pale complexion. “Well, from anyone, really. But yeah, Series Nine, custom firmware.” He flexed the fingers again, servos purring. “Got it after a little misunderstanding with a War-class unit. Long story short: he got my arm, I got his bounty.”

He gestured to a faint scar along his collarbone with the casual air of someone describing a paper cut. “Name’s Jax, by the way. And you’re clearly not your average scavenger if you can identify military-grade components on sight,” he continued, extending his organic hand.

“Kiri.” She was practically vibrating in her seat now, exhaustion forgotten. “This is Raelin. I study tech whenever I can get my hands on it. Manuals, salvage, anything.” Her words came faster, animated. “How’s the neural integration? Do you get phantom sensation feedback?”

Color had returned to Kiri’s cheeks, and she was sitting up straight for the first time in weeks. The rifle still made Raelin uneasy, but seeing Kiri’s excitement…

“Better than the original, honestly,” Jax said, wiggling his synthetic fingers. “Last week I could identify the grade of coolant leak just by touching a conduit. I’m thinking of entering flavor competitions.”

Kiri giggled, and Raelin felt something tight in his chest loosen slightly.

“What about power consumption?” she asked. “The specs I’ve seen suggest Series Nine units draw enormous amounts of…”

“That kind of tech must cost a fortune,” Raelin interrupted, voice carrying an edge he hadn’t intended.

Jax’s smile widened. “Yeah. One successful hunt pays for months of living expenses.” His tone grew quieter. “Course, you’ve got to survive to collect. Lost two partners last year. War-class units are getting smarter.”

Raelin couldn’t help himself. “Sounds like odds that don’t favor long careers.”

“You’re not wrong,” Jax agreed with a dark chuckle. “But when you’re Pointless or close to it, crazy starts looking like the only sane option. The Oracle doesn’t care who kills the robots, long as they’re dead.”

Kiri was about to respond when a soft chime echoed through the waiting area.

“Kiri Kestrel, please report to Examination Room Five.”

Raelin helped his sister to her feet, noting how she tried to hide the way her breathing hitched from the simple movement. Her moment of technological fascination faded as quickly as it had come, replaced by the familiar pallor and tremor. She looked longingly over her shoulder, but let herself be guided by her brother.

“Good luck!” Jax called after them.

Inside Examination Room Five was a middle-aged woman with graying hair pulled back in a practical bun. Her white coat bore the subtle insignia of the Medical Guild, a stylized caduceus crowned by the Oracle’s Eye, indicating she’d completed formal training rather than learning through apprenticeship like most Substructure professionals. She looked up from a slim tablet as they entered, her expression professionally warm, but assessing.

“Kiri, I presume? I’m Dr. Voss. Your brother mentioned some ongoing health concerns when he scheduled the appointment.”

Kiri nodded, her voice smaller than usual. “That’s me.”

The examination room was small but well-equipped, with a diagnostic scanner mounted on an articulated arm extending from the wall, protruding above an examination table. Various sensors and monitors lined the surfaces, their displays showing readiness indicators in soft blue and green. Dr. Voss gestured for her to lie down. Kiri’s eyes darted between the various monitors and sensors, her earlier fascination with technology now tinged with apprehension.

“How long have you been experiencing symptoms?” Dr. Voss asked, as Kiri settled onto the examination table.

“I’ve been getting tired easily,” Kiri explained. “Shortness of breath, sometimes chest pain. It’s been getting worse over the past few months, especially when I work.”

Dr. Voss nodded, making notes on her tablet. “Your records don’t show any family medical history. Do you know if either of your parents had heart problems?”

Raelin and Kiri exchanged glances. “We’re not sure,” Raelin answered. “Our parents died when we were young.”

“I see.” Dr. Voss turned to activate the diagnostic scanner, its sensors extending toward Kiri. “This will take just a few minutes. Try to relax and stay still.”

The scanner hummed as it moved around Kiri’s torso. Data streamed across the displays in real-time, and Raelin watched Dr. Voss’s expression grow more serious as the analysis progressed.

Kiri’s hand found his, gripping tight. Her palm was cold and clammy.

“Well,” Dr. Voss said finally, setting down her tablet. She turned the main display toward them.

Kiri’s heart floated in three-dimensional projection, certain areas highlighted in amber and red. Raelin stared at the image, not understanding the technical details but recognizing that the colors meant something was very wrong.

“The good news is that we have a definitive diagnosis,” Dr. Voss said. “The challenging news is the treatment requirements.”

“You have cardiomyopathy, Kiri. Specifically, dilated cardiomyopathy. The walls of your heart muscle have become weakened and enlarged, making it difficult for your heart to pump blood effectively.”

What little color remained drained from Kiri’s face as she stared at the image. “Is it…?” She couldn’t finish the question.

“It’s a progressive condition,” Dr. Voss explained gently. “Without treatment, it will continue to worsen. However, there are management options available.”

She pulled up another screen. “Short term, I can prescribe medications to help your heart work more efficiently. That should help with the fatigue and breathing problems.”

“And long term?” Raelin asked, though he already suspected the answer from the doctor’s hesitation.

Dr. Voss’s shoulders sagged slightly. “The definitive treatment would be surgical repair or replacement. But that level of cardiac surgery…” She gestured helplessly. “Requires facilities that aren’t available in the Substructure. Those procedures can only be performed in the upper tiers.”

Raelin’s jaw clenched, and he felt Kiri’s grip tightening in his hand.

“How long?” he asked quietly.

“With medication and careful management? Years, potentially. But she’ll need to avoid strenuous activity.” Dr. Voss paused, her eyes sharpening. “The stimulant use needs to stop immediately. PepUp puts enormous strain on an already compromised heart.”

Kiri looked down into her lap. “But without it, I can’t work. I can’t earn points,” she croaked.

“I understand the dilemma,” Dr. Voss said, laying a comforting arm on Kiri’s shoulder. “But continued use could trigger acute cardiac failure.”

Dr. Voss stepped back to her tablet, entering the prescription. “I’m prescribing a heart medication that should help significantly with your symptoms. It’s not inexpensive, but it’s within reach with careful budgeting.”

The prescription appeared on Kiri’s OmniLink with a soft chime. Raelin glanced at the cost and winced. It would consume a significant portion of their weekly points, but it was manageable if they kept finding power cores.

“Thank you, Dr. Voss,” Raelin said, helping Kiri down from the examination table. “For the diagnosis and for being honest about the options.”

Dr. Voss nodded. “Take care of yourself, Kiri. And come back if symptoms worsen.”

They found Jax finishing his own appointment in the corridor, his cybernetic arm opened to reveal the complex mechanisms inside while a technician ran diagnostics.

“Everything working properly?” Kiri asked, some of her earlier fascination returning despite the weight of her diagnosis.

“Better than expected,” Jax replied as the technician sealed the access panels. “Integration’s ahead of schedule.”

He noticed their subdued expressions. “Hope everything went well.”

“Manageable,” Raelin said carefully.

Jax nodded, seeming to understand they didn’t want to discuss details. “Well, if you ever want to talk tech,” he said to Kiri, “I’m usually around the Stockpile area in the evenings. Always good to meet someone who appreciates quality engineering.”

Outside the clinic, they walked in silence through the familiar bustle of evening Undertown. Kiri’s steps were slower now, her brief moment of energy fading.

“So,” she said finally, “I need surgery that costs more points than we’ll earn in our lifetimes.”

Raelin’s jaw tightened. “Not necessarily. We know where to find power cores now. High-value salvage.”

Kiri shot him a look that was equal parts hope and skepticism. “Even if we brought in cores regularly, it would take months to earn enough for advancement. And that’s assuming we don’t get caught or robbed.”

Raelin’s fingers drummed against his OmniLink’s implant site as they walked. “One core a week, maybe two if we’re careful. Different routes each time,” he calculated. “Mix it up with scrap metal and broken circuits to avoid suspicion.”

Their plotting was interrupted by the familiar aroma of caramelized root chips which drifted over them as they approached the vendor’s stall. Yesterday, Raelin had pulled Kiri away from this same spot, counting every point like it was their last breath. Today, he stopped.

“One portion,” he said, raising his hand in preparation to pay with his OmniLink.

Kiri’s mouth fell open. “Rae, we can’t…”

The points transferred with a soft chime before she could finish. The vendor grinned and handed over a steaming portion wrapped in salvaged foil to Kiri.

She stared at the warm package in her hands, then at her brother, eyes watering.

“You know what really struck me back there?” she said, taking a tentative bite. Her shoulders straightened slightly as the sweetness hit her system. “Watching Jax’s arm move, seeing all those diagnostic displays…”

She paused, savoring another bite. “Every piece of tech we saw today, the scanners, the AI, even those neural interfaces, they’re not magic. Someone built them.” Her voice grew stronger. “The only thing stopping us from having them is arbitrary rules and numbers.”

The pale, exhausted girl from the examination room was fading, replaced by the sharp-minded scavenger who could identify military-grade components at a glance.

“One core at a time,” he said quietly.

“Months, not years,” Kiri added, taking another bite. “Dr. Voss said I have some time. Let’s put it to good use.”

They walked in comfortable silence after that, sharing the treat between them. Around them, Undertown’s evening bustle continued its familiar rhythm, but for the first time in months, Raelin wasn’t just hearing the sounds of survival, but of life.

In the distance, The Shaft’s imposing silhouette rose toward the levels above. For the first time, it didn’t seem quite so impossibly tall.