I scanned the stone wall at the end of the tunnel with my "Wolf Eyes." Unlike the passage to the left, this one had been dug upward along the stone wall, suggesting that whoever was trapped here, having no other way out, chose the most difficult escape route.

The Fish Bone Temple tunnel initially slanted downward, winding through the ravines and natural karst caves within the hills. If someone had tried to escape by digging a vertical shaft upward from this tunnel, the straight-line distance would have been the longest, requiring the most extensive effort. Furthermore, this section of the mountain was riddled with natural erosion, leaving the interior honeycombed and prone to collapse—a last resort measure indeed.

I looked up, but just one glance was enough to extinguish all hope. Less than ten meters above, the passage was sealed by massive slabs of rock. These stones, which seemed to have materialized out of thin air, resembled a giant stone coffin, tightly enclosing the area. Being trapped there meant being utterly cut off from both heaven and earth.

Seeing no way forward, I retreated to the fork in the tunnel and explained the situation to Big Gold Tooth and Fatty. Having survived perilous situations together before, Fatty and I weren't overly panicked by our current strange predicament.

Seeing that we were not flustered, Big Gold Tooth also managed to calm down. Humans are strange creatures; panic spreads like the fastest virus in a crowd, but as long as the majority remain composed, it forms a firewall against its spread. Excessive panic clouds judgment. In my experience, as long as we could figure out how that bizarre stone wall appeared, we could find an exit; we wouldn't simply suffocate to death in here.

Big Gold Tooth blamed himself, saying, "Alas, it's all my fault for being too curious and insisting on coming in with you two. If I had stayed above to keep watch, there would have been someone to signal outside. Now all three of us are trapped; what are we going to do?"

I comforted him, "Jin Ye, don't be too nervous. We haven't reached the absolute end yet. Besides, even if you had stayed outside, it would have been useless. Those stone slabs must weigh tons; you couldn't move them without explosives."

Seeing my composure, Big Gold Tooth asked, "Master Hu seems very relaxed. Do you have a plan to get out? Please tell us so I can feel at ease. Truthfully, I’m so scared I'm about to wet myself; I’m just barely holding it together."

I laughed self-deprecatingly, "What kind of escape plan? We’ll take it one step at a time. If Heaven truly intended to take us, it would have done so in the Yellow River; we wouldn't have waited until now. I believe our time hasn't come yet; we will certainly find a way out."

Fatty grumbled, "I'd rather drown in the Yellow River and choke on silt than suffocate in a hole like a rat."

I told Fatty and Big Gold Tooth, "Don't panic. Three of these four tunnels are blocked. The remaining one should lead into the Underworld Hall of the Tang Dynasty tomb. Looking at the surroundings, the Feng Shui Master who built the Fish Bone Temple and dug these tunnels must have been trapped after returning from the Underworld Hall. Since we haven't found his remains, perhaps he found another way out. We won't know for sure until we check that Underworld Hall."

Fatty and Big Gold Tooth agreed immediately. This tunnel still had a long way to go before reaching the Underworld Hall. There was no time to waste; we had to go investigate the depths of that ancient tomb.

So, Fatty still led the way with the two geese in front, while Big Gold Tooth and I followed behind, crawling into the forward passage. As I crawled, I cursed inwardly, "Damn it, we’re having bad luck because of this tunnel. I thought this was a route charted by a master tomb robber decades ago, surely foolproof. Who knew such a simple tunnel would hold so many tricks? I was too arrogant. If we get out of this, I’ll learn my lesson and never be so reckless again."

Impulsiveness is, in fact, a major flaw in my character. I know it well, yet I can't change it. This personality is only suitable for a junior officer in the army; it’s utterly unsuitable for a Feng Shui Master. Ancient tombs are fraught with unimaginable dangers, with peril lurking in almost every corner. "Caution" should be the most indispensable bottom line in this line of work.

It suddenly occurred to me that if Shirley Yang were here, she certainly wouldn't have let us blunder forward and crawl into a tunnel like this. Alas, she is a rich woman; she’d never need to crawl through tunnels like a rat. I wonder how she is doing in America now, and if Professor Chen’s mental illness has been cured.

Just as my mind was wandering, Fatty called out from ahead, "Old Hu, we're about to pass through a karst cave here."

Hearing the sound of dripping water, I hurried forward. Fatty had already squeezed out of the tunnel. I followed and swept my Wolf Eyes around, seeing that we were standing on a pile of loose soil, likely debris dug out when previous explorers dug the side tunnels.

Big Gold Tooth emerged right after me. We looked around and realized we were in a narrow passage inside the mountain, not a karst cave. The dripping water sound seemed to come from further down the passage; perhaps that was the legendary Dragon Ridge Maze.

The tunnel continued through this narrow opening, extending at the exact same angle as before on the opposite side. Big Gold Tooth pointed towards the sound of dripping water and asked, "Listen, isn't there a large karst cave over there? Why didn't the man who built the Fish Bone Temple try to find a way through the caves instead of digging this tunnel with so much effort?"

I said to Big Gold Tooth, "The locals here call those caves the Maze. You can't even keep track of direction inside. How could one easily find an exit? However, since we haven't seen that predecessor's body, perhaps he gave up on escaping through the tunnels and entered the Maze. If that’s the case, whether we can get out is uncertain."

Fatty said, "Why worry about that? This tunnel isn't finished yet. I say we explore the Underworld Hall first. If there’s truly no way out, then we can consider going that way."

I countered, "You have an ulterior motive. I've never seen you this proactive. You must be thinking of finding treasures in the Underworld Hall. But why don't you realize that treasures are useless if we can't get out?"

Fatty argued, "I’m looking at this strategically. We don’t know if we can get out right now, but it’s a sure thing there are grave goods in the tomb’s Underworld Hall. Let’s not worry about escaping; let’s grab the artifacts, stuff them in our pockets, and then figure out how to leave. If we succeed, we're rich. If we fail, at least we die with valuable goods instead of as poor wretches."

I waved my hand, interrupting him, "Alright, stop talking. You can spout a whole speech from one sentence of mine. Save some energy to think about escaping, okay? We'll do as you say—we'll check the Underworld Hall first."

Fatty ushered the two large white geese into the tunnel and started to crawl in, but I quickly grabbed him, making him and Big Gold Tooth put on their makeshift gas masks. We were to watch the geese closely. The initial part of the tunnel connected to a natural vent in the mountain, and there seemed to be caves further off, so air quality shouldn't be an issue. But this final segment connected to the Underworld Hall, and I suspected there might be an upward path from beneath it. If this was the only exit from the tomb, the air would stagnate far longer than the time needed for circulation. We had to take precautions.

After donning our gas masks and soaking towels in our water canteens to wrap around our necks, Big Gold Tooth gave Fatty a jade pendant of Guanyin Bodhisattva for protection, and I gave Big Gold Tooth a paratrooper knife for self-defense.

With our minor preparations complete, the three of us crawled into the second segment of the tunnel. This section was extremely short, perhaps fifty meters forward, before turning sharply upward for another ten meters or so. Sure enough, we passed through a layer of green bricks.

The green bricks of the Tang tomb were only three or four palm-widths thick—these were the floor tiles. They could be pried up with a shovel or an iron chisel. These tiles were laid beneath the Underworld Hall; the rest of the floor and walls were constructed from large stones fixed with iron bars, the seams sealed with molten iron, making them completely airtight. Only a small, deliberately weak spot ("void") existed in the center of the Underworld Hall floor.

Later, starting from the Yuan Dynasty, this practice of leaving a "void" to trap winds changed significantly because these spots were too easy to breach. However, the tradition of leaving a "void" persisted into the Qing Dynasty, though minimized to only a few inches—too small for a person to pass through.

Overall, the structural integrity and luxury of Tang tombs ranked among the highest in Chinese history. Below the entrance path, there were several colossal stone gates, the structure was deep within the mountains, and the surroundings were fortified with massive stone walls—describing it as impregnable wouldn't be an exaggeration.

Above the void in Tang tombs, there was usually one or more mechanisms hidden within the tomb bricks. Once the bricks covering the void were broken, the mechanism would trigger. According to the Tang tomb layout, this could involve quicksand, crossbow traps (), stone stakes, or even collapsing trapdoors designed to seal the Underworld Hall completely, preferring to destroy the void meant to trap air and gather qi rather than allow grave robbers access to the burial artifacts.

The Feng Shui Master who entered before us had already triggered and defeated this mechanism, saving us a great deal of trouble and effort.

Fatty let the two white geese into the tunnel opening above us, letting them check the air quality in the Underworld Hall. We waited, crouching in the tunnel. I kept thinking about those stone walls blocking the passages—they seemed to materialize out of thin air. I had never heard of such a powerful mechanism. Was it a "Ghost Wall"? But the legendary Ghost Wall didn't look like this. What was so strange about this tomb? Who was the deceased? Did that Feng Shui Master manage to escape?

Just then, Fatty pulled the two white geese back. Seeing that nothing seemed amiss, he tugged at me. The three of us crawled out of the tunnel and entered the Underworld Hall. The scale of this tomb chamber was truly immense, covering nearly two hundred square meters. We illuminated the area with our Wolf Eyes and, after one look around, couldn't help but ask in unison, "In the Underworld Hall... where is the coffin?"