Courtyard Check-in: Starting with a Small World of Cultivation

At four o'clock in the morning on July 18, it was still pitch black.

Chen Yu stood at the entrance of the research institute carrying simple luggage, a grass-green jeep parked behind him. Lin Zhenhua and Su Hongmei were already there, along with a young technician named Xiao Wang wearing glasses, who was the technical support personnel for this mission.

"Is everyone here?" Lin Zhenhua glanced at his watch. "Get in the car; it'll be a five-hour drive."

The jeep sped through the streets of Beijing before dawn. Chen Yu sat in the back, watching the street scenes rushing past the window—the dim streetlights, the occasional bicycle passing by, and sanitation workers already sweeping the streets. The city was not yet fully awake, but early risers were already busy making a living.

"Chen Yu, have you brought all the materials you prepared?" Su Hongmei sat next to him, clutching a briefcase tightly in her hands.

"I've got everything." Chen Yu patted the canvas bag beside him. "Samples, handouts, and case study images are all in there."

Lin Zhenhua turned around and said, "Xiao Chen, don't be nervous when you get to the factory. General Manager Zhao has good workers, but he's impatient and speaks his mind. Just explain according to our plan, and I'll handle any problems that arise."

"Thank you, Engineer Lin."

As the car left Beijing, it gradually brightened. The scenery along the roadside changed from plains to hills, and the further north we went, the higher the mountains became. The jeep wound its way along the mountain road, with rolling green hills and deep valleys visible outside the window.

"This place is really remote." Xiao Wang looked out the window, a little nervous. "I heard that military factories are all located deep in the mountains, for secrecy."

"Yes, the factory we're going to, Factory 903, produces key components for aero engines," Lin Zhenhua said. "So this is a rare opportunity. Remember, when you get to the factory, don't ask what you shouldn't ask, and don't look at what you shouldn't look at."

At 9:30 a.m., the jeep finally entered the factory area after passing through three checkpoints. Factory 903 was larger than Chen Yu had imagined—the entire valley had been utilized, with rows of factory buildings built against the mountainside, towering chimneys, and the faint roar of machinery. Armed soldiers patrolled the factory area, creating a solemn atmosphere.

Chief Engineer Zhao was already waiting in front of the office building. He was an engineer in his fifties with gray hair, wearing a faded military uniform, but with sharp eyes and a straight back.

"Engineer Lin, you've finally arrived!" Chief Engineer Zhao strode forward to greet them. "This must be Comrade Chen Yu, right? A promising young man!"

"Hello, Chief Engineer Zhao." Chen Yu shook hands politely.

"Let's go to the conference room first; several key technical personnel from the factory are waiting."

There were already more than twenty people in the conference room, mostly technicians in their thirties and forties, with a few older engineers with gray hair. As they entered, everyone looked up, their eyes filled with curiosity and scrutiny.

Chief Engineer Zhao got straight to the point: "Everyone, these three experts are from the Beijing Nonferrous Metals Research Institute. They've brought the latest methods for observing material defects. The problem we recently discovered in our factory was found using this method. Over the next three days, everyone must study diligently and master this technology!"

After a brief introduction, Chen Yu stood on the podium. He took a deep breath, quietly activating his intermediate-level breath concealment technique, completely suppressing his inner tension.

"Comrades, good afternoon. I am Chen Yu. Today I am not going to talk about profound theories, but rather a set of observation methods—how to use our eyes to see the hidden problems in the materials."

He opened his lecture notes, but instead of reading from them, he started with a real-world example: "Last month, we discovered this in a batch of blade samples submitted by your factory for testing—"

A magnified photo of the engine blade appeared on the projector, and the hair-thin crack was clearly visible.

A collective gasp filled the conference room.

"Why didn't we find it with conventional flaw detection?" Chen Yu looked at everyone. "Because the crack has a special orientation, almost parallel to the surface, resulting in a very weak reflected signal. However, by shining light at a specific angle, combined with the observer's experience and judgment, we can detect the anomaly."

For the next two hours, Chen Yu systematically explained the principles, techniques, and practical applications of observation methods. His explanations were insightful yet easy to understand, supported by both theoretical frameworks and concrete examples. Initially, there were quiet murmurs in the meeting room, but the room gradually quieted down, leaving only the sound of pens scratching on paper and occasional questions.

While eating lunch in the factory canteen, several young technicians gathered around: "Engineer Chen, how exactly do you adjust the light angle you mentioned?" "How do you accumulate observational experience?" "Are there differences depending on the material?"

Chen Yu answered them one by one. He found that the technicians in these military factories had a solid foundation, sharp thinking, and asked very insightful questions.

The afternoon session was for hands-on practice. Factory 903 had prepared a special sample room containing various materials and parts—some were qualified products, and some were intentionally manufactured defective products. More than twenty technicians were divided into four groups and conducted observation and practice under the guidance of Chen Yu, Su Hongmei, Lin Zhenhua, and Xiao Wang.

Chen Yu made his rounds between the work groups, stopping occasionally to give instructions: "Engineer Li, shift the light a little more, yes, that's the angle." "Engineer Wang, pay attention to the color changes in this area, it should be uniform normally."

After an afternoon of work, the results were significant. Several technicians were already able to independently discover some hidden defects, although the speed was still slow, but they were heading in the right direction.

After dinner, Chief Engineer Zhao called Chen Yu to his office alone.

"Xiao Chen, have a seat." Chief Engineer Zhao poured him a cup of tea. "Today's training was very effective. I can see that you are truly capable."

"Chief Engineer Zhao, you flatter me."

"No need for praise," Chief Engineer Zhao said seriously. "Xiao Chen, I need your help—our factory has a batch of urgent parts that need to be delivered in three days. But the quality inspection found several problems with the parts, and we can't find the specific defects using conventional methods. Could you... work overtime tonight and take a look?"

Chen Yu hesitated for a moment: "Yes, but we need relevant technical data and samples."

"Everything is ready." Chief Engineer Zhao took a folder from the drawer. "These are the drawings and process requirements. The samples are in the lab next door. However..." He paused, "the purpose of this batch of parts is special and needs to be kept confidential. After you've looked at them, you can't take notes or take photos; you can only report verbally."

"I see."

In the laboratory, five parts were neatly arranged on the operating table. These were the outer casings of some kind of instrument, made of aluminum alloy with a specially treated surface. Chief Engineer Zhao said that all five parts showed weak stress concentration signals during pressure testing, but the specific location of the defects could not be found.

Chen Yu put on white gloves and quietly activated his Spiritual Eye Technique. Under his extraordinary vision, the microscopic structure of the parts was clearly visible. He picked up the first piece, adjusted the angle of the light, and examined it inch by inch.

Time ticked by. The lab was quiet, save for the occasional sound of Chen Yu moving samples. Chief Engineer Zhao stood at the door, not disturbing them.

An hour later, Chen Yu put down the first part: "Chief Engineer Zhao, this one has been found."

"where?"

"Here," Chen Yu pointed to an extremely well-hidden corner on the inside of the part, "there's a 0.2 mm pore inside, located right in the stress concentration zone. I suggest confirming it with an X-ray, and then scrapping it."

Chief Engineer Zhao leaned closer to examine it, then took out a magnifying glass to check carefully, finally spotting the almost invisible dot: "My God... how did you find it, so well hidden?"

"Experience plus skills." Chen Yu didn't elaborate.

Over the next three hours, Chen Yu inspected the remaining four parts. Three of them were indeed defective—one grain boundary crack and two areas of abnormal microstructure. The last one passed the inspection.

"This one is fine." Chen Yu put down the fifth part. "The abnormal signal from the pressure test might be due to equipment error."

Chief Engineer Zhao excitedly grasped Chen Yu's hand: "Xiao Chen, you've been a huge help! If this batch of parts had been delivered with defects, the consequences would have been unimaginable!"

"Of course." Chen Yu glanced at his watch; it was already 11 p.m. "Chief Engineer Zhao, if there's nothing else, I'll head back to rest."

"Yes, yes, go and rest. We have training tomorrow."

Back in his room at the guesthouse, Chen Yu didn't rest immediately. He sat cross-legged on the bed and entered his small world to cultivate. Today's exertion had been considerable, and he needed to recover.

After cultivating for an hour, he exited the small world and was about to lie down to rest when his spiritual sense suddenly detected something unusual—there was someone outside the window!

This wasn't an ordinary worker; the person's footsteps were extremely light, and their breathing was deep and even, clearly indicating they had martial arts training. Moreover... there were faint fluctuations of spiritual energy emanating from them!

Chen Yu's heart skipped a beat, and he silently moved to the window. He activated the intermediate-level concealment technique at full power, and his spiritual sense probed out like a thread.

Outside the window stood a man in his thirties, dressed in military uniform, but with a demeanor different from that of an ordinary soldier. He was standing under a tree outside Chen Yu's window, seemingly smoking, but his eyes were actually scanning the surroundings, as if he were on guard duty or monitoring the situation.

What surprised Chen Yu even more was that he was very familiar with this person's spiritual energy fluctuations—it was the aura of obsidian! Although it was very weak, this person must have been in contact with obsidian, and not for long!

Are there cultivators in Factory 903? Or is there fire obsidian?

Chen Yu retreated to the bed, pretending to sleep, but his spiritual sense remained firmly locked onto the person outside the window. The person stood there for about half an hour, then turned and left, disappearing into the night.

"It seems Factory 903 is no ordinary facility," Chen Yu mused. Why would a military factory deep in the mountains have cultivators there? And why is there the aura of obsidian?

The training continued on the second day. Chen Yu noticed several unfamiliar faces among the technicians from the previous day—all young men in their thirties, with sharp eyes, not talkative, but quick learners. Among them was the man outside the window last night, who introduced himself as "Engineer Liu," and said he worked in the quality control department.

During a training break, Chen Yu casually asked, "Engineer Liu, what equipment does your quality control department usually use?"

"We have the standard equipment: X-ray machines, ultrasonic flaw detectors, and metallurgical microscopes," Mr. Liu replied fluently. "But for some special materials, these devices have limited effectiveness."

"for example?"

"For example, some new composite materials, and some..." Engineer Liu paused, "...parts for special purposes."

Chen Yu nodded without asking further questions. However, he noticed that Liu Gong's right hand had thick calluses on the web of his hand, which were not from holding a pen or operating instruments, but rather from holding some kind of cold weapon for a long time.

The next two days of training went smoothly. Chen Yu's method was validated at Factory 903—after the technicians mastered it, they discovered several previously undetected hidden dangers. Chief Engineer Zhao was overjoyed, calling it a "major technological breakthrough."

On the afternoon of the third day, before the training ended, Chief Engineer Zhao announced: "After deliberation by the factory's Party Committee, we have officially adopted the observation method proposed by Comrade Chen Yu and incorporated it into our factory's quality inspection standards and procedures. At the same time, we have appointed Comrade Chen Yu as our factory's technical consultant, who will come to the factory regularly to provide guidance."

A round of enthusiastic applause filled the conference room. Lin Zhenhua and Su Hongmei were both happy for Chen Yu—this was not only a personal honor, but also an achievement for the research institute.

Before leaving Factory 903, Chief Engineer Zhao privately approached Chen Yu: "Little Chen, there's something I'd like to ask you."

"Please speak."

"Our factory has some... special materials research projects," Chief Engineer Zhao said in a low voice, "and we've encountered some technical bottlenecks. If you're interested, you can participate next time you come. Of course, there will be corresponding benefits and confidentiality requirements."

Special materials? Chen Yu immediately thought of obsidian and Engineer Liu from last night.

"I'm very interested," Chen Yu said, "but I need to understand the project details first to see if I'm capable of handling it."

"Of course." Chief Engineer Zhao handed over an envelope. "This is preliminary data. Take a look at it when you get back. Be careful to keep it confidential."

On the way back to Beijing in the jeep, Lin Zhenhua excitedly said, "Xiao Chen, our institute has really made a name for itself this time! Technical advisor for Factory 903—that's a golden opportunity!"

"It's the result of everyone's joint efforts," Chen Yu said modestly.

Looking at the mountain scenery outside the window, Su Hongmei suddenly said, "Chen Yu, don't you think that Engineer Liu is a bit strange?"

"What's so strange?"

"I can't explain it." Su Hongmei shook her head. "He learns very quickly. He grasps some techniques instantly, as if... he has similar experience."

Chen Yu's heart skipped a beat. Although Su Hongmei didn't understand cultivation, her keen observation skills allowed her to sense the anomaly.

When he returned to the courtyard house that evening, it was already dark. Qin Huairu was cooking, and seeing him come back, she quickly started making noodles: "Are you hungry? Eat something first."

"Where are the children?"

"She's asleep." Qin Huairu brought over some noodles. "While you were gone, Xiaotian asked every day when his father was coming back."

After finishing his meal, Chen Yu entered his small world. He didn't immediately begin cultivating; instead, he took out the envelope that Chief Engineer Zhao had given him.

Inside were several pages of classified documents, the contents of which were very brief. They only stated that Factory 903 was researching "new high-temperature resistant materials" and needed to solve the problem of "microstructural stability." The document included a blurry photograph—it was a black metal sample with dark red textures on its surface.

Obsidian alloy? Chen Yu recognized it immediately. Factory 903 was trying to incorporate obsidian into metal materials to create high-temperature resistant alloys!

No wonder his observation method is needed—the structure of this new material must be very special, and conventional detection methods are difficult to grasp.

Chen Yu felt both excited and wary. He was excited because this might be an excellent opportunity to access cultivation materials; he was wary because Factory 903 clearly had connections with the cultivation world, and that Engineer Liu might be a cultivator sent to protect or monitor them.

After leaving the small world, Chen Yu contacted the fake man number one.

"Master, in the few days you were away, three groups of suspicious people appeared near the courtyard," reported False Man Number One. "Two groups are police officers, investigating the remaining associates of Yan Bugui's case. The third group... is cultivators, secretly monitoring the courtyard."

"A cultivator? What are their characteristics?"

"A man and a woman, the man had a scar on his face, and the woman had short hair. They rented a house nearby and took turns monitoring each other every day."

Scarface! He really was spying on me!

"What actions are they taking?"

"Nothing for now, just surveillance. But last night, that man went to the western suburbs and met with two other practitioners. I couldn't hear what they were saying, but they mentioned 'southern Yunnan' and 'the end of the month'."

The end of the month? Chen Yu remembered Scarface saying in Guangzhou, "I need ten pieces of obsidian before the end of the month." Today is July 20th, ten days until the end of the month.

It seems Scarface is preparing for some big operation, and time is of the essence.

"Continue surveillance, but be careful not to expose yourself."

"Yes."

Chen Yu lay in bed, his mind racing. The special materials research at Factory 903, Scarface's surveillance operations, the end-of-month deadline... all these clues seemed to point in the same direction—the ancient cave dwelling of the cultivators in southern Yunnan.

Is obsidian the key to entering the cave? Or is there something inside the cave that requires obsidian to open?

He decided to break through to the ninth level of the Qi Refining stage by the end of the month. Every bit of strength he gained would increase his safety.

Outside the window, the moonlight was as clear as water.

Chen Yu knew that peaceful days were numbered.