In the Liuhu Wetland Park, outside a long-abandoned sanatorium, rough-hewn wooden stakes of varying sizes stood erect in the ground.
"I heard that freshly cut timber, if not properly treated, can crack and warp," said Lao Bai, frowning as he surveyed the raw logs haphazardly stacked against the wall, an axe in hand.
Fang Chang inquired, "How is it typically treated?"
Lao Bai replied, "The moisture is dried out through heating, or the ends are painted to help the wood dry naturally. It can also be soaked in water, but that makes it harder to handle afterward… let's just hope it doesn't rain in the next few days."
After a quick assessment, Lao Bai estimated that, including the work from yesterday, cutting the logs into 3-4 meter lengths and sharpening both ends to be driven into the earth would more than suffice to build walls on the northern and western sides of the sanatorium.
However, these were untreated raw logs, and their durability was uncertain; a few more rains could render them useless.
After some discussion, he and Fang Chang decided to shift their approach and use cement as a building material.
There was an abundance of concrete debris scattered across the wasteland, and even more within the ruins of the sanatorium itself.
Years of erosion, thermal expansion and contraction, and the ravages of wind and rain had reduced most of these concrete chunks—peeled from their steel reinforcements—into gravel.
Trusting in the integrity of these materials was unrealistic.
Nevertheless, mixing the rubble with cement and reinforcing it with steel rods salvaged from the ruins would still make it possible to construct a rudimentary concrete structure.
Though it might not be a fortress, it was certainly sturdier than wood.
After all, they weren't building a skyscraper.
However, to use this concrete debris, they would first need cement.
To make cement, they would require a significant amount of coal and a furnace capable of withstanding temperatures of up to 1450 degrees Celsius.
At just that moment, Kuangfeng and Ye Shi returned.
Fang Chang noticed that Kuangfeng was carrying a plastic bucket filled to the brim with smooth, uniform mud.
"There's a river to the east of Liuhu," Kuangfeng explained, "One not marked on the map, likely formed in the past two hundred years. We've explored the entire eastern and southern shorelines, and we've marked the areas where mutant creatures are active, as well as potential nests, on the map."
As he spoke, Kuangfeng gestured for Ye Shi to unroll a map, on which charcoal had been used to mark various notations.
With this map, they could now safely retrieve water from the lake's edge.
Yet Fang Chang's attention was fixed on the bucket in Kuangfeng's hands.
"What's in the bucket?"
"I found this by the river," Kuangfeng set the bucket down and continued, "I had an idea—it could be used as a building material, so I brought it back."
"This won't work as a building material," Lao Bai squatted down and scooped some of the mud with his fingers, rubbing it between his thumb and forefinger. His face suddenly lit up with excitement. "But this... this is a good find. Our kiln is settled."
"A kiln?" Ye Shi asked, confused.
"I talked it over with Lao Bai. We're going to make cement," Fang Chang explained.
Kuangfeng looked at him, stunned.
"Can it really work?"
"Why not? This is a sandbox game, after all," Lao Bai stood up enthusiastically. "Just pour the mud here, and you two can fetch a few more buckets. Fang Chang, gather some twigs. Hurry up."
"Got it!" Fang Chang said with renewed energy, rushing off.
Kuangfeng and Ye Shi exchanged a glance, their faces equally bewildered, and followed suit.
…
The river wasn't deep, but there was plenty of mud on its banks, and it was close enough to the sanatorium that it took little effort to gather a large amount.
Lao Bai formed a circular mound from the mud, digging two holes on the sides for ventilation, and then filled the center with charcoal and dry leaves from earlier fires, lighting it with the matches the manager had left behind.
The fire quickly ignited.
The surrounding mud began to dry out.
As Lao Bai dug more mud, he continued to build up the furnace walls, working until it reached the height of his thighs, before he started feeding thumb-thick sticks into the furnace.
"What's this for?" Fang Chang asked, curious. Although he had played survival games before, he had never done anything this detailed in one.
"Charcoal production. We don't have coal, so we'll use charcoal instead. You can't smelt cement with wood, so we'll start with the basics," Lao Bai replied.
"You actually know how to do this?"
"I used to do it back home when I was young."
"..."
So, you used to play with fire as a kid?
Lao Bai stood up and patted his hands together. Taking advantage of the fire not yet catching the wood, he began sealing the furnace.
At that moment, Chu Guang suddenly recalled the second son of the Yu family, who had previously mentioned a marriage proposal to him, and felt a bit awkward.
Even if, hypothetically, there were no shelter 404, no system, no players, and he was left to integrate into the local society... he could never bring himself to do it!
He was too thin.
Maybe after two more years of growth...
"Is there something you need?" Chu Guang asked in a calm tone.
Yu Xiaoyu stretched out her arm, which had been hidden behind her back.
Only then did Chu Guang notice she was holding a small blackish flatbread, which, judging by its texture, was likely made from mashed green wheat.
"My second brother asked me to give this to you. He told me to say I made it for you." Her words were carefully enunciated.
The convoluted subject-verb relationship had Chu Guang puzzled for a moment, until he finally pieced it together—it was Yu Hu who had asked her to bring him the flatbread.
"Thank you?"
"No need," Yu Xiaoyu said, handing the flatbread to Chu Guang before turning and dashing off, leaving him bewildered in the wind.
…
In the present world.
Jinling.
Riveting his helmet off, Yan Feng rubbed the bridge of his nose and began searching the bedside cabinet. After a moment, he found his glasses and put them on.
Sitting on the edge of his bed, he paused for a moment, gathering his thoughts before heading to the bathroom to wash up. He then donned his jacket, went downstairs, and leisurely rode his bicycle to the cafeteria.
The time was 5:30 AM.
Aside from students preparing for the graduate exams, few people came to the cafeteria at this hour. The entire hall was nearly empty, with only a few windows near the door still open for business.
The cafeteria lady, busy behind the counter, immediately recognized him and greeted him with a smile.
"Professor Yan, you're here so early today."
"Mm, went to bed early last night… two buns, please."
"The buns have just been steamed; you'll need to wait a moment."
"No rush."
Yan Feng took out his meal card and scanned it at the reader.
The steam rising from the bamboo basket was fragrant.
Yan Feng relished the smell—it was comforting. But unfortunately, for someone like him who wore glasses, it was less than ideal.
He removed his glasses and wiped off the fog. As he did, his thoughts drifted to his character in *Wasteland OL*.
Though his starting strength was a bit lower, in comparison to his real-world self, his virtual counterpart was far stronger.
And most importantly, that character didn't suffer from myopia.
At that moment, someone tapped him on the shoulder.
Turning around, he saw Professor Wang Haiyang standing there.
"Have class this morning?"
"No class, just woke up early."
"I thought physicists like you would burn the midnight oil."
"That's a misconception; I rarely bring work home," Yan Feng pushed his glasses up and suddenly remembered something. Looking at him, he asked, "By the way, there's something I'd like to consult with you."
Professor Wang Haiyang raised an eyebrow.
"Is this about yesterday's topic?"
Yan Feng nodded.
"Yeah."
"Hold on, let me ask you first. This novel you're talking about… it wouldn't happen to be your own work, would it?" Wang Haiyang smiled and added, "With novels, it's best if they're somewhat ambiguous. If they're too realistic, they lose their charm."
"Actually, it's not a novel... to be honest, it's... a game."
"A game?"
"Yeah," Yan Feng took the buns from the cafeteria lady, unwrapped them, and took a bite. "An apocalypse-themed game."
Professor Wang Haiyang seemed intrigued. "Can you elaborate?"
"I don't know much more than you do; the game is still in closed beta, so I can only tell you so much." Yan Feng paused. "But tell me, what kind of society would need to operate without even having a fixed power source?"
"No power source?" Wang Haiyang paused, then smiled. "Are you suggesting that remote power delivery could replace a fixed source?"
"Is that difficult?" Yan Feng asked.
"I'm not sure, but from my perspective... wireless power isn't the hard part. The real challenge lies in sourcing cheap, clean energy. Even if energy loss reaches 90% or more, the costs need to remain reasonable."
Wang Haiyang stopped, then added with a chuckle, "Unless we're talking about controlled nuclear fusion, I can't think of a better solution."
Nuclear fusion?
Yan