Apocalypse: I Built the Infinite Train

Chapter 128: The Water Purifier

Lin Xian was surprised as he accepted the box. "Level-2 Purified Water Standard… That’s the Federation Phoenix’s standard, right?"

"Yeah," Xu Jin confirmed, pulling out a silver-colored detection device. "This is one of their research-grade instruments, including the Soul Wave Detector. We traded Eerie Blood Crystals for it aboard the Silver Star. That train stocked up on tons of supplies from the Phoenix’s mobile rescue points, including some light industrial manufacturing equipment. Compared to our older devices, this one is a lot more precise."

"There should be Federation Phoenix personnel stationed at the spaceport," he added, "but I’m not sure if we can trade with them."

Lin Xian thought for a moment, then returned to his train and filled a cup of water from the onboard purifier before stepping back out. "Brother Xu, test this for me."

Xu Jin nodded. "Is this from your train’s water purification system? Alright, I’ll check it out."

He casually placed the silver detector into the cup. After a few seconds, a green light flashed on the device.

Lin Xian assumed this meant the test was complete, but to his surprise, Xu Jin, Shu Qin, and Old Mo all froze, their faces changing drastically.

"Level-1 Purified Water?!!"

"What the…?!"

Old Mo pushed down his sunglasses, his expression filled with disbelief. "Kid, did you just distill this water?"

"No," Lin Xian replied, confused. "It’s just filtered through the purifier."

Xu Jin and Shu Qin exchanged stunned glances. "That’s impossible," Xu Jin said. "Even the highest-end purifiers can only get water down to Level-2. Unless you immediately distill it, it naturally degrades after an hour. There’s no way it should stay at Level-1 purity!"

"Is that true?" Lin Xian frowned.

To verify, he turned toward Chen Sixuan. "Ms. Chen, bring me a bottle of sealed water."

She nodded and quickly fetched an unopened bottle of drinking water. Lin Xian poured some into a new cup and handed it to Xu Jin.

"It won’t work," Xu Jin said as he ran the test. "Even sealed bottled water can’t escape the effects of Nightfall Infection."

Sure enough, the device lit up with a yellow light.

"See? Green is Level-1, yellow is Level-2, and orange or red means the water is completely unsafe to drink."

Lin Xian’s brow furrowed.

So even the cleanest factory-sealed water was corrupted by Nightfall, yet somehow… his train’s water purifier produced purer water than bottled water?

What the hell?

If water became contaminated after an hour, then there was only one way to confirm his theory—he needed to filter bottled water through his purifier, then wait for an hour.

If the water remained at Level-1, then that meant the Eerie Cube truly blocked the Nightfall Infection!

"Captain Lin, what model is your purifier? How is it able to directly produce Level-1 Purified Water?"

Xu Jin and Shu Qin’s eyes were burning with curiosity.

Even though boiling water could improve its safety, it would never reach Level-1 purity. Only distillation could achieve that, but distillation consumed a ton of energy, making it impractical for most convoys.

For the majority of survivors, as long as their water was drinkable and wouldn’t kill them, they were willing to settle for Level-2 Purified Water.

Yet Lin Xian’s purifier?

It could bypass distillation entirely and still produce Level-1 water—meaning he could drink the cleanest water anytime, anywhere.

This wasn’t just advanced equipment—this was a luxury in the apocalypse!

"I found it along the way," Lin Xian said vaguely, seeing their eager expressions. Then, after a pause, he added, "But I have extra units. If you want one, I’m willing to trade for Eerie Blood Crystals."

Making these purifiers wasn’t particularly difficult for Lin Xian. Keeping them to himself didn’t make much sense. Instead, he could exchange them for more Blood Crystals—which were far more valuable for survival and strength.

Currently, the Infinite Train only had two Blood Crystals:

• One Level-1 Blood Crystal was installed in the radio station.
• One Level-2 Blood Crystal was inside the Soul Wave Detector.

He had none to spare.

"Seriously?!"

Xu Jin’s eyes gleamed. "How many do you have?"

"Two," Lin Xian replied. "But I need to dismantle them first."

"Two?! You lucky bastard!" Old Mo whistled. "How many Blood Crystals do you want for one?"

Xu Jin and Shu Qin exchanged glances. "Our two convoys can share one purifier," Shu Qin suggested. "That way, we’ll have three purifiers in total, which is enough. But we don’t have many Blood Crystals—only small ones. I heard large eerie entities drop bigger ones, but we can’t handle those."

One hundred survivors sharing one Level-1 purifier and two Level-2 purifiers was more than enough. Their priority was to give the purest water to children and the wounded, reducing their risk of Nightfall Infection.

Xu Jin took out five small Blood Crystals, some of which had been traded from others.

Lin Xian inspected them—they were Level-1 Eerie Blood Crystals, likely from creatures on the same level as the Red Centipede, Fog Spider, or Three-Headed Monster.

His estimation of their convoy’s strength rose—they weren’t weak. Clearly, having a large team was a major advantage.

"Alright," Lin Xian agreed. "Three crystals for one purifier."

"Deal!" Xu Jin and Shu Qin agreed instantly, handing over three Blood Crystals.

Without hesitation, Old Mo reached into his pocket and pulled out a metal case.

Inside were four Blood Crystals.

"For Xiao Le and the others to have clean water," he said gruffly. "I’m getting one too!"

Lin Xian nodded and accepted six Blood Crystals in total.

He returned to the Infinite Train, and about ten minutes later, he and Luo Ye carried out two large purifiers.

The A1-Class Subcritical Reverse Osmosis Purifier was significantly bulkier than Shu Qin’s original one.

The moment it was brought out, dozens of convoy members gathered around, their eyes filled with amazement.

"Holy crap, this thing looks high-tech as hell!"

"This has to be top-tier Federation equipment…"

"I bet it’s worth a fortune!"

Xu Jin and Shu Qin wasted no time. Their teams carefully loaded the purifier onto their heavy trucks, where all critical survival gear was stored.

"Seriously, thank you," Shu Qin said, genuinely grateful. She glanced toward Lin Xian’s train, a flicker of yearning in her eyes.

"You’ve been running non-stop," she sighed. "Honestly… if we ever got the chance, I’d love for my entire convoy to join your train. Surviving out here is just too damn hard."

Lin Xian fell silent.

He had thought about it before—what if he extended his train, adding more survival carriages?

In theory, his train could accommodate far more people.

Then there was the Silver Star, and Dragon Mountain No.1, both of which had been modified into massive, moving cities.

That was his original dream, wasn’t it?

Hearing Shu Qin’s words…

Lin Xian couldn’t help but seriously consider the idea once again.