When Pei Ran returned underground, she saw a hazy silhouette in the smoke near the front of the train.
It was Jiang and Aisha emerging from the driver's cab—Jiang was crawling beneath the locomotive again.
The old lady was still making bold, sweeping repairs to the train.
Beside them, a new cart had appeared, piled high with tools and spare parts. Aisha pointed at the cart, then at the door Pei Ran had previously ripped open on the platform—it had come from inside.
Not long after, Jiang climbed back out, sitting on the tracks amid the smoke, coughing, her head bowed in thought, as if unsure of something.
Aisha crouched down and began gesturing solemnly to her grandmother again, pointing at her fingers one by one. Jiang responded in the same manner.
Pei Ran studied their hands. "They're using a lot of fingers, even pointing at different joints... Looks like a code—maybe letters."
W was analyzing it too. "That's likely."
If each joint on ten fingers corresponded to a letter, then tapping out letters could form syllables, which could string together into entire sentences.
It worked, but the pace was excruciatingly slow—just saying one sentence would take forever.
Jiang, meanwhile, turned to Pei Ran, pointed at her own head, and shook it, visibly frustrated.
Her expression said it all: the retrofit project had happened decades ago, and now she couldn't remember everything clearly.
Pei Ran immediately asked in her mind, "W, do you have the blueprints for the Night Sea No. 7 locomotive?"
"Of course," W replied. "Give me a second."
Pei Ran knew he'd have to strip all the text off the blueprints first.
But W's "second" was practically instantaneous. Pei Ran's wristband received a complete set of images in the blink of an eye.
She instantly pulled them up on the holographic display, enlarging the screen and moving it in front of Jiang.
It was a detailed set of blueprints for the Night Sea No. 7 locomotive—one sheet after another, extremely comprehensive.
Jiang froze in disbelief when she saw what was on Pei Ran's screen.
Her face said it clearly: How is this even possible?
She flipped through the blueprints page by page, her astonishment growing.
They weren't just complete—they were even more detailed than what she'd had during the original retrofit project. Every part of the engine, every control circuit, relevant or not—it was all here.
She'd been struggling with the repairs, but now it felt like heaven had dropped a miracle in her lap.
Jiang looked back at Pei Ran, puzzled. This girl—what was her background? How on earth had she obtained something like this?
Aisha's eyes widened too. She didn't need to sign anything—Pei Ran could tell exactly what she wanted to say: This is insane. Where did you get this?
Pei Ran thought to herself, Forget just the blueprints for Night Sea No. 7—W probably even has the plumbing diagram for your house.
Jiang kept flipping through until her finger stopped on the last one.
The final image wasn't a traditional 2D blueprint—it was a full 3D structural model of the locomotive.
It recreated the engine's interior in perfect detail. Every part could be zoomed in, rotated, even dissected. It was so intricate, it felt like a complete virtual replica of the train.
You could locate any part, zoom in from any angle, and see everything clearly. It was absurdly convenient.
Back when she worked on the retrofit of Night Sea No. 7, they'd never had anything remotely this advanced.
Jiang looked at Pei Ran again, her astonishment plain as day.
This wasn't someone who had merely found old files—her data was far superior to what anyone had had back then.
Pei Ran saw the look on her face and understood immediately.
"W, did you build that 3D model yourself?"
"Mhm," W replied casually. "Since I wasn't in charge of the repair plan, I figured I'd just throw together a model using their blueprints."
It had taken him less than a second.
He wasn't doing the repairs himself and was bored—so he decided to show off a little.
With the blueprints in hand, Jiang's problem was solved in no time.
She grabbed her tools and ducked back under the train.
A while later, she emerged again, visibly more relaxed. She gestured to Pei Ran and Aisha, beckoning them back to the cab.
Inside, the scorched wiring on the control panel had all been sorted and reconnected.
Jiang took the driver's seat and began flipping a row of switches on the panel.
A soft humming rose from the floor beneath them, followed by a faint vibration.
Pei Ran and Aisha looked to Jiang, who gave them a small smile and a thumbs-up.
The train was fixed.
Aisha couldn't speak, but her excitement showed—she threw one arm around her grandmother and the other around Pei Ran, bouncing on the spot with joy.
Jiang allowed the hug for a moment, then gently pried Aisha's arm off and motioned for them to get ready.
The smoke was thickening. The fire was spreading. They had to move—now.
There was a horn on the train, but no one knew if sounding it counted as "making a noise." It resembled a fire alarm and probably wouldn't trigger a punishment, but why take that kind of risk?
The smoke below was so thick, you couldn't see the other cars—no way to know if anyone was still on the platform.
Pei Ran grabbed a wrench from the toolbox, leaned out the door, and banged it hard against the metal wall of the carriage.
CLANG—
CLANG—
CLANG—
The metallic strikes echoed through the smoke-filled station.
If anyone was still out there, she hoped they understood what it meant: the train was leaving.
Jiang waited a moment, then pulled one lever and nudged another forward.
Night Sea No. 7 began to move.
The train rolled silently forward, gradually picking up speed, finally departing from the terminal and entering the tunnel.
The entire city was out of power. The tunnel was pitch black, but small emergency lights still flickered at intervals.
Those dim yellow bulbs, one after another, told the people in the cab that there was still a way forward—that this was not an endless abyss.
Once the train was running smoothly, Jiang rested her elbows on the console and rubbed her temples, eyes closed. She was old, and she'd been working hard all day—she was tired.
Pei Ran nudged Aisha and pointed to the cars in the back, motioning for her to take Jiang to rest.
Aisha caught on quickly and helped her grandmother up.
Before leaving, Jiang pointed at the levers on the console and silently asked Pei Ran: Do you know how to drive this thing?
Anyone else, and Jiang would've been certain the answer was no—this was an ancient train, after all. But Pei Ran was different. She'd produced incredibly detailed blueprints out of nowhere. Who knew what she was capable of?
Pei Ran nodded confidently.
Jiang was instantly reassured and left with Aisha through the door at the rear of the cab.
Pei Ran set down her backpack, placed the metal sphere on the console, and took the driver's seat.
Even without W's guidance, just watching Jiang's movements had been enough for her to figure out how the train worked.
She ran her hand over the levers and said to W, "Driving a train seems easy—no steering wheel. I guess this lever starts it, that one stops it. If you just keep a constant speed, there's not much else to do."
W disagreed, defending train drivers everywhere: "Driving isn't the hard part. A driver's real job is to constantly monitor for malfunctions, make emergency decisions, read signals, and follow dozens of operating rules. It's way more complicated than you think."
Pei Ran stared into the darkness ahead. "In times like these, are there still signals to read? Or rules to follow?"
They both fell silent.
This was the end of everything. There were no more signals, no more rules—only a lonely antique train gliding through the burning city's underground tunnel.
They traveled a while longer before a white glow appeared in the distance, growing larger.
The tunnel's exit was near.
Leaving the tunnel meant leaving Night Sea's city center.
But the smoke followed. Though the doors were shut, it still seeped in through the gaps.
The light grew until the arched outline of the tunnel's exit came into view.
Night Sea No. 7 burst from the darkness.
Suddenly everything was bright—yet still shrouded in a smoky gray. Buildings in the distance were reduced to blurry shadows. The fire in Night Sea had spread so far that even the outskirts were thick with smoke. The tracks ahead vanished into the haze.
A cold wind swept through, thinning the smoke just slightly.
Then W shouted, "Pei Ran! Brake!!"
She saw it too. Not far ahead, something massive was sprawled across the tracks—an excavator, positioned dead center.
Pei Ran yanked the brake.
The train screeched violently, steel grinding against steel with a horrible wail.
They were too close. It might be too late.
Whoever had left that excavator there had picked the perfect ambush point—right outside the tunnel, where the light would blind and the smoke would hide everything. By the time a driver saw it, it'd be too late to stop.
If they hit it, the train would derail—especially the front car.
The green light within her—the one that could write words—had been dormant, but now jolted awake, trembling inside her mind, ready to act.
But before it moved, someone appeared beside her.
Aisha.
She had entered the cab too, and saw the same danger ahead. She stepped beside Pei Ran, calm and focused, lifting both hands in front of her chest.
She crossed her ring and pinky fingers like braided cords, held her middle fingers straight, looped her index fingers over them, and pressed her thumbs against the top—middle fingers pointed forward.
A seal.
A faint green glow gathered at her fingertips. The hand sign moved slightly.
BOOM.
Pei Ran saw the excavator up ahead suddenly flip into the air, hurled aside by an invisible force.
She turned to stare at Aisha once more.
W spoke up. "A fusion unit."
Aisha was also a fusion unit.
The track ahead was now clear.
Just then, something strange burst out of the smoke in the distance, clattering down the rail line toward them.
It looked like a digger—kind of—but not quite.
The thing was a haphazard assemblage of excavator parts, like someone had cobbled it together with whatever was lying around. Its body was an excavator cockpit; multiple buckets served as its legs, and several more were mounted up top like arms. It stumbled forward in a chaotic mess of limbs, waving its makeshift claws like a drunken crab as it charged at Night Sea No. 7.
W said, "It's CT122."
Pei Ran got a clear look at it too. This mechanical monster wasn't one of those deranged bio-fusion units—it had no signs of integrated biological tissue. Its core was a dark blue sphere: one of the Public Security Bureau's patrol bots. Its ID number had been scratched off, its casing punched through with holes, and its bottom half was pried open and spliced into various digger parts.
It was that indestructible little ball. Stubborn. W's relative. The clingy, never-say-die AI—CT122.
Yesterday, W had shot it in the forest. Not only had it survived, it had followed them all the way to Night Sea in secret, upgraded itself into this abomination, and apparently devised a clever plan to block the train.
It really was getting smarter.
Its goal hadn't changed:
To eliminate her—the highly dangerous L15-level threat.
Single-minded. Obsessive.
So obsessive, it didn't care that derailing the train might kill the regular passengers in the rear cars.
W zoomed in with the scanner and quickly said, "Look at that transparent panel in front of it—one corner still has the Public Security Bureau emblem. My weapons can't penetrate it."
The little ball had been hit twice by W's bullets before. This time, it had added a shield. A large one. It covered the bot completely—good for defense, but it also blocked its own line of fire. No wonder it had come to block the tracks directly.
Aisha spotted the mechanical monster too. She hesitated for a moment, then formed another hand sign.
Unfortunately, the effect was much weaker this time. Her gesture only caused some stones to burst up from the tracks at CT122's feet, making it stagger briefly.
She had already used her green light once and couldn't use it again so soon.
Pei Ran's green light was already primed.
Writing was dangerous—but only when done in the real world. This time, she only needed to write in her mind. There was no other option. She had to risk it.
Focusing on the incoming CT122, Pei Ran summoned the green light and wrote two characters in her thoughts:
[Blow Away.]
She needed to blast it off the tracks so Night Sea No. 7 could keep moving.
In the air, some invisible force solidified.
CT122 suddenly halted mid-step—then, in the next second, it flew straight up into the air, arms and legs flailing.
It flipped in midair, and the cobbled-together excavator parts tore apart, as if ripped by some overwhelming force. They scattered in all directions, breaking apart mid-flight.
Both "blow" and "away" worked perfectly.
Turns out, writing inside her mind was safe. Pei Ran remained unharmed.
This time, she also discovered something else.
Just like Aisha's ability, hers could also target enemies from a distance—it didn't affect her surroundings at all.
And it could bypass obstacles like the train's windshield.
That dark blue little ball of CT122 was hurled skyward, spinning high up into the air. Who knew where it landed. Pei Ran didn't bother to find out. She slammed the throttle.
Night Sea No. 7 accelerated, leaving the shredded mechanical creature far behind.
Aisha looked stunned. She turned to Pei Ran, momentarily forgetting her custom sign language. Her eyes sparkled with joy.
As if she'd just found someone like her.
Pei Ran hadn't shown her green light, but there was no one else here. The mechanical monster had charged straight down the track at the front of the train—those in the rear cars wouldn't have seen a thing.
So the only one who could have blown it away was Pei Ran.
The view ahead rapidly cleared. The smoke thinned. The train had reached the outskirts of the city.
The burning Night Sea was behind them. On either side of the tracks, only a few scattered factories remained. The rails stretched straight forward into the distance.
Aisha let out a breath, then began tapping her fingers like crazy. After a few seconds, she frowned—apparently the sentence was too complex. She gave up and opened her wristband's virtual screen.
She pulled up the sketchpad and carefully drew a stick figure.
The little person had a circle for a head, two dots for eyes, and arms and legs jutting out like mismatched twigs.
W leaned over to look with Pei Ran and remarked dryly, "I'm starting to believe the saying—birds of a feather really do flock together."
Aisha's drawing skills were about equal to Pei Ran's. A true match in mediocrity.
Aisha then drew two vertical lines beside the little person, then stacked blocks and mounds beside them like uneven tombs.
W frowned. "What's this supposed to be?"
Pei Ran, reasoning it out, said, "It's obviously a road, with collapsed buildings on both sides. She's saying she was walking through it in the past couple of days—some buildings had fallen. Your comprehension's kind of weak."
W: "…"
Just like how the best tutor for a struggling student isn't the top of the class, but someone who just figured it out—same thought process.
And in this case, it took one terrible artist to truly understand another.
Aisha's stick figure walked among the mounds. Suddenly, a green dot floated down from the sky, landing inside the little figure. Then the stick arms twisted into a new shape, and the rocks on the road flew away.
Pei Ran understood. That was how Aisha received her hand-sign ability.
Her power was clearly destructive—W had called these "Collapse"-type abilities before.
But then again, maybe not.
Pei Ran's own "Order"-based power could also manifest as raw force. It looked like a "Collapse"-type on the surface, but it wasn't.
Aisha stopped drawing and lifted her hands again to demonstrate her signs to Pei Ran.
Her fingers moved fast and fluidly, looping through intricate motions, forming one strange hand sign after another.
Although she had only received her green light ability recently, there was no way she had just started learning these signs. She was way too practiced—she'd clearly been doing this for some time.
Pei Ran silently grabbed Aisha's arm and turned her to face the front of the train.
If you're handling a weapon, best not to point it at people.