“Its name is T1.”
Yoon Youngsu proudly pulled down the gray waterproof tarp.
“......!”
“You’re wondering what the hell this thing even is, right?”
“Uh... honestly, yes.”
The ominously named T1 turret looked like a large rectangular metal box a little over 1.5 meters wide and about 60 to 70 centimeters tall and deep.
From the front, where the two barrels stuck out, it had the shape of an isosceles trapezoid.
From the side, aside from a vent and a fixed access latch, it was basically just a smooth metal box.
“Made it out of aluminum alloy and stainless steel. If it’s gonna stand up to all four seasons, snow, rain, wind, all of it, this shape is best. Still doesn’t have the outer shell on yet. Gonna cover it with a waterproof camouflage tarp.”
Clank!
When Baek Hail undid the latch and lifted the upper cover, the complicated interior finally came into view, with two air rifles mounted side by side inside.
“See this motor here? ◈ Nоvеlіgһт ◈ (Continue reading) Harmonic-drive servo motor. This is what rotates the turret a full three-sixty.”
Pointing to another motor, Baek Hail continued,
“This one’s a high-precision BLDC motor. Handles vertical tilt, plus or minus thirty degrees.”
“Response time is 0.8 to 1.1 seconds,” Yoon Youngsu chimed in. “If it’s already acquired the target and tracking it, it gets a little faster. That’s the power of the motors and the program.”
“The magazine runs on a solenoid system. Magazine ain’t really the right word, though. More like automatic pellet feeding. Anyway, the whole thing weighs a little over twenty kilos, so we can install it at the guard posts too. Or on the shelter roof, on top of the walls. Hell, if we do the camouflage, concealment, and cover right, we could even put one down by the main gate approach. Youngsu.”
“Yes, sensei. Ahem.”
Called on by name, Yoon Youngsu rested a hand on the T1 and picked up where Baek Hail left off.
“The T1 turret operates based on the real-time video feed from the high-performance PTZ cameras you installed at the guard posts, boss, plus laser rangefinder data.”
“I know that much already.”
“Ah—sorry. Anyway, the effective range on the new air rifle Mr. Baek made for the T1 is 180 meters, right?”
“That’s right.”
“But if Akina helps correct for it, two hundred meters is no problem.”
“Oh?”
“For real?”
When both Junho and Baek Hail showed interest, Yoon Youngsu got even more excited.
“Yep. Through the real-time data link, it calculates muzzle velocity, air resistance, target movement, all of it, and adjusts the firing point. Basically, the microcontroller and servo controller I tuned by hand get used ridiculously well by Akina. Raspberry Pi 5 and the Jetson Orin Nano hooked up to the PWM-supported servo-control board and—”
Junho immediately cut off the humanities-kid abuse he was being subjected to for the first time in a while.
“So can this thing attack cars or drones too?”
“Yes. It can calculate the direction of movement and fire ahead of the target.”
“Lead shooting.”
“Yeah, that. Anyway, whether it’s a car or a drone, they’re usually not gonna come charging in from the start at sixty or seventy kilometers an hour, right? Especially drones. If they’re scouting, they fly at cruising speed and their direction stays steady. Cars are on roads, so it’s easy enough to predict and shoot.”
“Good.”
Smiling, Junho turned to Baek Hail.
“So this gets mounted on the ground drones too—the ones made by modifying the kids’ electric carts, right? Weight’s not a problem?”
“No problem. Even though those are for the kids, they’re built to handle fifty kilos. Made for two riders, front and back. Even with this and an industrial air tank loaded on, it doesn’t go over thirty. So...”
Baek Hail pointed to a pile of metal stacked in one corner of the workshop.
“That’s AR500 steel plate. We use that to wrap the front and sides of the cart in armor plating, it’ll come out right at forty kilos.”
“What about speed and operating time?”
“With the motor modified, top speed’s twenty kilometers an hour for about thirty, maybe forty minutes. But it’s not like we’re gonna be moving at that speed constantly while firing, right?”
“Right.”
Just like the T1 turret itself, the ground drone with a T1 mounted on an electric cart was, for now, a defensive platform.
Even when it moved, it would usually be at a slow walking pace.
“So it’s fine to think of it as about an hour. If we add more battery, we could probably get another twenty minutes, but then it gets heavier and puts strain on the frame.”
“As it is now is perfect.”
There was basically no scenario where they would be moving this electric ground drone around and fighting with it for over an hour.
More than anything—
“Copying the air rifles is easy now, right?”
“Yeah. Can make ten a day. If Jeongwoo helps as assistant, probably twenty.”
“Then let’s make around a hundred for the guard posts, the shelter-defense turrets, and the electric ground drones. We’ve got plenty of carts anyway.”
They just had to make a lot and rotate them in and out if something happened.
“Exactly. When I saw you buying fifty carts at a time that my son was supposed to ride, I was wondering what the hell you were thinking. Figures you already had a plan.”
“If we’re going to use them for years, we’ll obviously need parts too. For now, make ten electric ground drones.”
“Got it. Youngsu, your programming and all that’s ready, right?”
“Yep. It’s linked with Akina already. Just need to squash a few bugs. First setup’s a little complicated and takes a bit of time, but it’s deep learning after all. Once we test it a few times and fix the errors, it’ll speed right up.”
Junho nodded.
“Good. Don’t rush it too much. Nobody’s coming this far for the time being anyway, so we’re fine. If zombies enter our zone, Junhyeok or I can just go kill them.”
“Yeah. Even being generous, three or four days, tops. After that, sensei and Mr. Choi can just crank them out.”
At Yoon Youngsu’s words, Baek Hail stared at him in disbelief.
“You think you just crank these out and that’s it? It’s not like there’s only one or two motors in the damn thing. You got any idea how hard all that fine sensor tuning of yours is? Huh? Fine. Tuning.”
“But if you record the work process and input the result values, Akina corrects for that too.”
“What? Seriously?”
Baek Hail’s eyes went wide, and Yoon Youngsu tilted his head.
“No, sensei, you seriously didn’t know that yet? Ah, this won’t do.”
With his trademark punchable face, Yoon Youngsu fiddled with the small laptop in his hands and went on,
“Fine tuning? That’s, like, one of Akina’s specialty moves. Just record it with the CCTV and the workbench cameras. Then it analyzes all the sensor data generated during assembly in real time and gives you the optimal correction values. Motor torque? Sensor sensitivity? Akina finds it herself and applies it to the control system. No need for Mr. Baek to go through endless trial and error one by one.”
“Holy shit...”
“I’m telling you, it can automatically control the machines and equipment in the workshop that are connected to the network too. You’ve got a bunch of CCTV cameras in here already, right? Through those and the sensors, it gives live feedback in real time. It can even handle turret-placement optimization, drone mission assignment, and optimal control across the board.”
“Seriously? That’s insane...”
Now even more puffed up with pride, Yoon Youngsu pointed at the laptop screen.
“Mr. Choi and sensei just have to build. It can catch equipment malfunctions and damage too by fusing vision AI with sensor data. And this’ll help you too, boss.”
“Hm...?”
Yoon Youngsu turned to the puzzled Junho and continued confidently.
“From now on, if you fight anywhere the shelter drones or CCTV can see, it won’t just be shooting at whatever moves. It’ll judge what’s more dangerous, where it’s most efficient to hit, and Akina will calculate the optimal firing solution in real time and feed it to you.”
With a grin like some scheming villain behind the curtain, Yoon Youngsu added,
“Every time she tests and operates, she builds more data and keeps learning on her own, so performance keeps improving. The deep-learning model updates in real time, so even if it stumbles a little at first, after just a few runs it’ll process things way faster and more accurately than a human. So once the initial setup’s done and we feed it enough data, after that we won’t need to keep adjusting it by hand. It’ll handle everything on its own.”
“So when’s all that actually going to be done?”
“...Ah.”
At Junho’s coldly practical point, Yoon Youngsu froze, then awkwardly looked away and answered,
“Maybe... two months? Or three?”
“......!”
Junho involuntarily flinched.
Whether it was two months or three, if what Yoon Youngsu was saying became reality...
Then all he had to do was make one for sniping use and use it.
When a human judged and fired, wind speed, wind direction, and other conditions made the trajectory unstable past a certain range, so the effective range topped out at 180 meters.
But if AI handled the fire control, then two hundred meters was a sure thing, and depending on the situation, maybe it could even stretch another twenty or thirty beyond that.
Of course, because the power was higher than what they were using now, the number of shots a portable air tank could fire would drop below ten, and the noise would be a little louder too.
But in a sniping situation, he would be firing from a pretty long distance anyway, and with drone-assisted perimeter observation, that would not be much of a problem.
Junho was pleased inside, but it was rare to see the usually cocky Yoon Youngsu shrink like this.
So he deliberately let out a small laugh and said,
“Youngsu, focus on finishing the turret and drone work first.”
“Yes...”
“Khh-heh-heh! See that, you little bastard? Hurry up and go write your program.”
“All. Right. Got it. Tch. Just you wait...”
His pride wounded in a truly bizarre way, Yoon Youngsu trudged off toward the main building where the control room was, reciting the exact kind of line defeated villains always used while making their escape.
***
Three more days passed after that.
During that time, Baek Hail, using Choi Jeongwoo as his assistant and working with AI support, stayed up late into the night and finished ten twin-barrel T1 turrets first.
The completed T1 turrets passed their testing in the underground firing range without any problems.
So Junho loaded them onto a multipurpose electric cart and went around the rear-mountain guard posts with Choi Jeongwoo, installing them one by one.
“Aren’t they heavy, sir?”
“Not really.”
Watching Junho carry a turret weighing over twenty kilos and a six-kilo industrial oxygen cylinder at the same time, then stride up the slope like it was nothing, Choi Jeongwoo was startled.
But now that he was a full shelter member and understood very well what kind of person Junho was, unlike on the first day, he felt almost no fear.
He simply watched Junho’s back with pure admiration and a reassuring sense of trust.
His daughter Choi Jiwoo was not merely safe.
After eating breakfast until she was stuffed, she was now studying together with the Kim siblings under Baek Sua, who had actually attended one of Seoul’s top pharmacy schools.
They had personal tablets loaded with every textbook and reference book needed for compulsory education.
On top of that, there were enough notebooks, pens, and other supplies to last dozens of people for years.
Seeing all the school and office supplies laid out as if someone had looted an entire stationery store, Choi Jeongwoo had been deeply impressed.
And when he heard they had, in fact, looted a stationery store that had been about to go out of business, he had no choice but to shake his head in amazement.
What was more, the small-built but capable-looking future sister-in-law(?) taking care of his daughter and Kim Junseo beside Baek Sua—
being from an orphanage herself, she was a master at handling kids like Jiwoo and Junseo.
Honestly, he found himself thinking she might even be better than a daycare teacher.
Anyway, the food, the play, the education—aside from toddler clothing, almost everything was practically perfect.
And Choi Jeongwoo felt something beyond mere satisfaction, something close to being moved.
Jaeyoung... you don’t have to worry about our Jiwoo anymore.
The thought of his dead wife suddenly darkened his mood, but Choi Jeongwoo gave a light shake of his head, adjusted the equipment bag on his shoulder, and kept climbing diligently after Junho.
In a world that had become hell...
If his beloved daughter could go on living in this heaven-like place called our shelter, he could do anything.
***
A day later, Choi Uisu and Kim Heeyoung finally left the nursing home and came to the shelter.
For the nursing home’s safety, Junho had provided them with one air rifle weaker than the ones used at the shelter, with an effective range of around one hundred meters.
Go Seokjin was a former army staff sergeant, Go Jeongnam had hunting experience from his younger days with both shotguns and air rifles, and Lee Jaeseok was at least a military veteran too, so with proper training there was no real problem in having them use an air rifle.
In any case, Hanaareum Nursing Home now had one PTZ camera and four domestic wide-angle CCTV cameras installed.
That meant that during the day, they could identify anything approaching the nursing home from within an eight-hundred-meter radius, and at night from within three hundred meters.
They had also installed a relay and simple communications equipment.
That meant the nursing home could contact the shelter control room at any time, and the control room could also directly manage some of the systems there, including the nursing home’s power.
It was a safeguard in case looters or some hostile group ever seized the place.
Of course, Junho had not actually told them that part.
Still, it was obvious to anyone watching that he was genuinely supporting the nursing home in earnest.
So the people there were sincerely grateful to him.
And so, after turning the nursing home—which in the old timeline would have burned down into ruins—into Forward Outpost Number One for Gahyeon-ri, Junho brought two new members into the container residential zone of our shelter:
Choi Uisu, former head of emergency medicine who had also completed a subspecialty in trauma surgery.
And Kim Heeyoung, a former head nurse who had worked over twenty years in a general hospital, with broad experience across internal medicine, surgery, pediatrics, OB-GYN, and the ER.
“You’ll stay here for about a week. This is where people live while adjusting before moving into the shelter proper.”
“Ah... I see.”
The couple, already surprised to learn that the old rusted iron gate blocking the approach road—despite the several No Entry signs hanging on it—was actually a blast door using advanced technology,
then saw the long container blocking the road split open to both sides like an automatic gate, and they stood there with their mouths hanging open just as Choi Jeongwoo once had.
And once they stepped inside and saw there were more than ten container homes,
and that despite the shabby-looking exterior, the insides were furnished as well as any decently equipped studio apartment,
they finally seemed to relax and trust Junho completely.
“Bedtime, wake-up time, and meal times are set. Basic food is in the fridge. Since this is a place where more than ten people are living together, there has to be at least a minimum of time discipline. And...”
As Choi Uisu nodded along while listening to Junho explain the shelter’s rules and points of caution, he asked,
“I understand what you expect from us, but medical practice has limits unless the equipment and facilities are properly in place. So with that in mind...”
“What do you need?”
“...Excuse me?”
“Ah, actually, I should probably tell you first what we already have.”
Bringing up the list of medical equipment and facilities they had previously purchased from the Volcano Group on the tablet screen, Junho said,
“For starters, we have defibrillators, ECG monitors, oxygen generators, and suction machines. There’s a full set of suturing and minor surgical equipment. We also have medical sterilizers, sterile workstations, electrocautery devices, UV disinfecting units, and operating tables. Just in case, we prepared two or three sets of everything.”
“......!”
“For diagnostic equipment... we’ve got automatic blood-pressure monitors, blood analyzers, installed and portable X-ray equipment, ultrasound diagnostic machines, things like that. We also have IV sets and syringes, plus pharmaceutical refrigerators and freezers. Naturally there’s a large supply of both basic medications and prescription drugs. You can search the full list on the tablet.”
“N-no...”
“My God. How did you prepare all of that?”
To the stunned Choi Uisu and Kim Heeyoung, Junho answered calmly,
“Who knows. And I told you before, didn’t I? That this would probably be the safest and best place to live in South Korea right now. Then of course it needs to be equipped to this degree.”
“God...”
“Unbelievable...”
Whirrr...
The couple, still wearing expressions of stunned disbelief, turned their heads at the sudden mechanical sound.
A container on the opposite side from where they had entered was slowly opening.
Glancing that way, Junho let out a small laugh.
“Looks like the kids from our shelter came over to visit. I guess after living here for quite a while, they’re comfortable with this place.”
The children and the two dogs who had ridden in the front passenger seat and rear cargo bed of the multipurpose electric cart Baek Sua had driven came tumbling out.
The smallest girl immediately took off running around the yard with the black dog.
“Jiwoo! Choi Jiwoo! You’re gonna fall!”
There were Purdy and Kkamsoonie—better than people in some ways—and CCTV everywhere, so it was safe, but just in case, Kim Hayoon, who always stayed with the two children and watched over them, raised her voice.
“Oh my, how adorable.”
The couple smiled softly as they watched carefree little Choi Jiwoo.
But then Kim Junseo followed behind her, looking a little downcast.
And the moment they saw Kim Hayoon, small-framed and walking quickly at the side of the tall Baek Sua—
“......!!!”
Their eyes flew wide open almost in unison.
“Y-Yuna...?”
In a trembling voice, as if she could not believe it herself, Kim Heeyoung called out the name of the daughter who had died six years ago.
