The Hall of Underworld, since ancient times, was the designated place for the tomb master's sarcophagus. The Burial Sutra explicitly states that the Hall of Underworld, also known as the Hall of Tranquility (), is the core of the mausoleum. Whether for a joint burial or a solitary one, the tomb master should lie within the coffin, clad in full burial attire, covered further by the outer shell (). Even if the body, for whatever reason, could not be placed inside the coffin and shell, the deceased's attire, headwear, and footwear from their lifetime would still be interred within them.

In short, the body might be absent, but the coffin and shell were invariably present in the resting chamber. Furthermore, throughout history, no Tomb Raider Captain (), after breaching the mound gate and digging the shaft, ever hauled the sarcophagus out. Besides, the space within the tunnel was limited; even a small coffin could not possibly be extracted through it.

My worldview was shattered again. I racked my brains, unable to fathom the reason. Could it be that the tomb master’s sarcophagus had evaporated into the air within this Hall of Underworld?

All three of us were quite astonished. Da Jinya’s mind was quick; he stood behind me and reminded me, "Master Hu, look around this Hall of Underworld. Besides the missing sarcophagus, what else seems amiss?"

I swept the hall with my wolf-eye lantern, examining every inch, above, below, left, and right. Not only was the sarcophagus gone, but the hall was utterly empty. The floor was bare; not a single funerary object, not even an extra piece of stone.

Yet, judging by the scale and structure of the Hall of Underworld, this was unequivocally a paramount Tang Dynasty princely tomb. The architecture followed the principle of a square base and a round top—square and grounded below, with clean angles and precise structure, and the upper section resembling the domed roof of a Mongolian yurt—a perfect representation of the ancient Chinese concept of Tian Yuan Di Fang (Heaven is round, Earth is square), perfectly aligning with the cosmological views of the time.

On the floor of the Hall of Underworld, there were six stone stands, all empty. But Da Jinya and I knew these were meant to hold the six ritual jades—the cong, gui, zhang, bi, hu, and huang—used for sacrifices to the Six Directions. This was an honor reserved only for Imperial family members.

The four walls of the Hall of Underworld were not entirely bare, though. They held only preliminary wall paintings, all simple line drawings (white drawings) that had not yet been colored in. They depicted the sun, moon, and stars, with the main focus being thirteen palace maids. These maids held brocade boxes, jade pitchers, or musical instruments. They were all depicted as plump and full, painting a vivid scroll of Tang Dynasty court life.

Since all the murals were merely outlined and uncolored, I had never encountered anything like it. I asked Da Jinya, hoping his decades of experience dealing with antiques might shed some light on the meaning.

Da Jinya also shook his head repeatedly, "Truly bizarre. Judging by these murals, this tomb was absolutely meant to house an extremely important figure from the court, and a female at that—perhaps a Consort or a Grand Princess. But these murals…"

Seeing Da Jinya trail off mid-sentence, I knew he was uncertain, so I asked, "The murals aren't finished? They just started and then stopped?"

Da Jinya nodded when I suggested this, "Yes, they aren't finished. But this is too unconventional… no, it's not just unconventional, it’s completely illogical."

A royal mausoleum being halted mid-construction was extremely rare. Even if the tomb owner suffered a political downfall, became a victim of court intrigue, or was executed for treason, they would usually still be interred with their appropriate status. Such a grand tomb undoubtedly belonged to an Imperial relative, and the Emperors understood that family scandals should remain private. Affairs within the palace seldom leaked; those who needed to be eliminated were dealt with, and the burial proceeded as usual.

Seeing that lingering here yielded no answers, I took out a candle and lit it in the southeast corner of the Hall of Underworld. Though the light was faint, the flame burned straight up, showing no sign of flickering out. Reassured, I called Da Jinya and Fatty to check out the Front Hall.

To conserve energy, we only used one flashlight. Fortunately, the chamber was empty, so there was no worry about tripping over anything. The three of us, leading the two large white geese, passed through the stone doorway of the Hall of Underworld and entered the Front Hall.

In the layout of ancient Chinese mausoleums, the Hall of Underworld was paramount, with the Front Hall secondary. The arrangement of the Front Hall traditionally followed the principle of "serving the deceased as if they were alive"—a mandate passed down from earlier dynasties, continuing until the late Qing period, differing only in scale.

The Front Hall was designed to mirror the living quarters of the tomb master. If the master lived in a palace, the Front Hall had to emulate that actual palace. Of course, apart from the Emperor himself, other Imperial relatives could only have a section of their residence replicated in the Front Hall; it was impossible to perfectly duplicate the dwelling for every single relative. Only an Emperor who had ascended the throne and possessed the Great Treasure could command such a monumental undertaking.

Although Da Jinya, Fatty, and I were all in this trade, we had never actually encountered a genuine grand tomb like this. Today was a stroke of luck to stumble upon one. If we were to undertake the excavation ourselves, we would never touch a tomb of this magnitude; at most, we’d target a noble or prince's grave.

This was partly because we lacked the sophisticated means to dig a tunnel that cut directly into a void space. Another reason was that we actively avoided tombs of this scale. Any single item unearthed from here could cause an earth-shattering sensation, attracting too much trouble. My plan was always to find a few in the deep mountains, earn enough money, and be done with it.

Today was a sheer accident—we found an existing tunnel, granting us entry into this massive tomb. Beforehand, we never anticipated the Hall of Underworld would be empty, and that the tunnel we used to enter was inexplicably sealed. Heading to the Front Hall was merely an attempt to find clues and figure out how to leave.

As the three of us entered the Front Hall, we were once again stunned. The Front Hall was even larger, but all the pavilions and halls were only half-built, the work stopped abruptly and remaining so until this day.

The Front Hall was indeed constructed to resemble ancient palaces, but crucial sections were unfinished, merely showing the skeletal framework. The stone door leading to the underground palace was sealed, the surrounding walls constructed of massive stone blocks, with molten iron poured into the seams and reinforced by iron bars as thick as duck eggs. On the floor of the Front Hall section of the underground palace, there was a small fountain pool, from which water still bubbled forth robustly.

I pointed to the fountain and said to Da Jinya, "Look at this small fountain. This is what is colloquially known as the 'Coffin Spring.' In a tomb with favorable Feng Shui, having such a spring is truly supreme fortune. The Dragon Vein also relies on the surrounding topography. When I first examined the Feng Shui outside this ancient tomb, I felt that while it possessed a Dragon Vein, erosion by wind and rain had spoiled the mountain’s contours, turning what was once an auspicious dragon into a vulnerable, unprotected one. However, looking now, the topography here features a rare Nei Zang Yuan (Internal Hidden Pool). There is a spring within the acupuncture point, and the flow of this spring remains perpetually the same—it never overflows, nor does it dry up. This gives the site the quality of Qi Chu Zhi Xiang (a vessel storing essence). Its source is celestial, its flow like water ripples. This Nei Zang Yuan is exceptionally suited for burying a female; her descendants will surely benefit from her blessing."

Da Jinya remarked, "Oh, so this is the 'Coffin Spring' we talk about? I've heard of it but never seen it. If the Feng Shui topography is intact, then it’s even stranger—why was the interior construction only half-finished? And why wasn't the tomb master laid to rest?"

I replied, "Strange things happen every year, but today is particularly abundant. Even here in the Front Hall, it's unfinished. It’s truly hard to comprehend."

Fatty offered, "I don't think it's that strange. Maybe they ran into wartime chaos, or perhaps the expenses became too great, and the finances couldn't sustain such a massive construction project, forcing them to stop building such a huge mausoleum."

Da Jinya and I both shook our heads. I said, "Absolutely not. Halting construction halfway and relocating the tomb is terribly inauspicious for the principal. Moreover, the person who selected the site would face execution of their entire clan (). Firstly, this treasure location has no issues from a Feng Shui perspective—it's concealed and hidden, making it difficult for tomb robbers to discover, and it’s a rare Nei Zang Yuan. They wouldn't abandon this half-built mausoleum for another, better site. Nor would it be due to war or disaster; if that were the case, they wouldn't have sealed the underground palace with nothing inside. It doesn't seem like they were trying to guard against tomb raiders."

Da Jinya agreed with my view, "Correct. Judging by the way the tomb walls and stone door were sealed, they did not leave in a hurry after stopping work; rather, they calmly secured the underground palace, with no intention of reopening for construction later. Otherwise, simply opening that stone door would be a significant undertaking, and there must be at least four other large stone doors of similar scale outside this one."

But what force compelled the builders to abandon this mausoleum? There must have been an unavoidable reason, but we couldn't solve the riddle; we simply couldn't guess.

It seemed the predecessor who disguised their entrance by building the Fishbone Temple and cutting a tunnel into the Hall of Underworld was fooled by an empty tomb, just like us. We didn't find his body here; perhaps he already found a way out.

Having found nothing in the Front Hall, we had no choice but to return along the path, planning to take one last look at the Rear Hall and the side accessory chambers. If we found nothing there either, we would have to return to the tunnel and navigate our way out through the labyrinthine Dragon Ridge Labyrinth ().

The three of us walked and talked, all feeling that this tomb was unusually eerie, with too many aspects that defied logic. I began telling them, "There’s the ancient concept of decoy tombs—Cao Cao and Zhu Hongwu both used them—but this Tang Dynasty tomb is definitely not a decoy. Inside here…"

As I spoke, we walked back into the Hall of Underworld. My sentence was cut short when Fatty suddenly interrupted me. Da Jinya also placed a finger to his lips in a gesture for silence. I looked up and saw, in the southeast corner of the Hall of Underworld, just behind the glow of the candle, a 'figure' had appeared.