The swarm of piranhas arrived swiftly, the sound of their shearing teeth like wave after relentless wave of surf, growing from a distant murmur until the first few were nipping at the edges of the bamboo raft beneath our feet. Though the raft was tightly lashed, it couldn't withstand the gnawing assault of those ravenous, devil-spawned piranhas.

In our desperation, we were forced to swing our entrenching tools to hack at the nearest fish. The moment one shovel plunged into the water, it was seized by the piranhas, fighting like rabid dogs. I yanked my arm back sharply, tossing the two attached creatures aside, and looked down, a cold sweat instantly plastering my shirt—under the beam of the climbing helmet’s spotlight, the razor-sharp edge of the stainless steel shovel blade was already marked with several intersecting rows of bite impressions.

Yet, these were only the first few fish to reach us. A much larger host was surging from behind. If we didn't take decisive action, the raft would be chewed into splinters by the horde within seconds. But the raft was still a dozen meters from the exit of the Mushroom Rock Cave, and we were completely surrounded by the piranhas; there was no way to use paddles, making those final ten meters feel like an eternity stretching across hell itself—a distance we feared we would never cover.

Fatty shouted in panic, “We’re finished now, I’ll be damned if I end up as fish bait! Old Hu, do you have any bullets left in that pistol? Just put one straight through my heart; I’d rather be shot dead than be gnawed alive by these man-eaters.”

I was starting to lose my nerve too. Gritting my teeth, I told Fatty, “Fine, we’ll do it your way. I’ll shoot you first, then I’ll shoot myself. We absolutely will not fall alive into the enemy’s hands.”

At that critical juncture, hanging between life and death, Shirley Yang suddenly spoke with complete composure, “Look at the pair of cowards you two have become! Usually, you spout torrents of boasts, projecting ferocity and arrogance, acting as if nothing in the world is worthy of your regard. Now, before we’ve even passed Shalong Mountain, you’re thinking of suicide over such a small predicament! Think of the shame you’ll face when you return and have to speak to the world about your exploits. Now, everyone listen to my orders.”

With that, she raised her pistol and fired several shots into the densest concentration of piranhas in the water. The river instantly turned scarlet with fish blood. Seeing the fresh blood, the surrounding piranhas—regardless of whether they were kin or not—went into a frenzy, surging forward to tear at the wounded fish. The immediate danger of the raft being shredded eased slightly.

Shirley Yang didn't bother putting the pistol away; she simply let go, allowing the Type 64 to drop into the water. At the same instant, she hurled the grappling hook, which she had long aimed at the cave exit, toward the Mushroom Rock. The steel cable of the hook wrapped three times around one of the rock pillars of the Mushroom Rock, the claws locking firmly onto the stone.

She ordered Fatty and me to grab the grappling hook’s steel cable and haul the raft rapidly toward the bank near the cave entrance. Under the combined pull of the three of us, the raft’s speed was several times faster than when we had been flailing wildly with the entrenching tools. When we were about five or six meters out, Fatty began tossing our geological backpacks—laden with equipment—and both insect nets one after the other onto the bank. Each bag weighed forty or fifty pounds; removing one lightened the raft considerably, increasing its speed with every toss.

Just then, the sound of shearing teeth intensified dramatically; the massive school of piranhas was swarming after us like maggots clinging to flesh. We dared not linger on the raft any longer and leaped onto the bank composed of ancient Baiyun rock sediment. The instant our feet touched the shore, the ropes binding the raft snapped behind us. The entire structure disintegrated, the bamboo poles floating away, and the damaged high-powered spotlight sank with them.

The piranha school devoured the water fleas clinging to the bamboo but lingered nearby, unwilling to leave. Watching the fish churning in the water, I let out a deep sigh of relief. We hadn't ended up as fish food; otherwise, we would have perished in this water-filled cavern before even seeing the Tomb of King Xian.

Fatty suddenly yelped beside me, “Oh no! My backpack fell into the river!”

I glanced over and was startled myself—we had thrown the three large rucksacks onto the bank, but before we could retrieve them, the first bag we threw, which landed farthest from the bank, couldn't be supported by the loose stones near the edge and tumbled into the river. Since there was no stable footing there, retrieving the bag meant going into the water. The large pack was already beginning to drift away with the current, and the massive school of piranhas was lurking nearby.

When we set out, we had categorized all our gear; this specific backpack held the butane injection canister, capable of firing a burst of flame two or three times when paired with a lighter. Since it was hard to acquire, we only had this one bottle, originally intended for use inside the tomb in case of emergency. Furthermore, the bag contained six oxygen cylinders the size of canteens, along with a measuring scale, diving goggles, and a respirator—all indispensable underwater gear for raiding the Tomb of King Xian, which was built in the middle of a lake. Beyond that were many other crucial items. It was precisely because the bag contained equipment filled with various gases that it hadn't sunk entirely yet.

If this pack were lost, we might as well pack up our tails between our legs and retreat home immediately. Shirley Yang was also frantic seeing this. She wanted to use the grappling hook to snag the bag, but the hook was still firmly entangled on the Mushroom Rock, impossible to free in our haste.

I knew that any further delay meant the equipment would be swept away beyond recovery. Holding only the entrenching tool, I spotted a fissure on the reverse slope of a rock near the bank. Without a second thought, I jammed the entire shovel blade upright into the crack, using the tool like a wedge, and forced it horizontally until the shovel was wedged tightly in the stone fissure. Testing it, I found it remarkably secure, so I suspended my entire body over the river, gripping the triangular handle of the entrenching tool with one hand while reaching down into the water with the other to grab the backpack as it floated directly beneath me.

Only when the pack was firmly grasped in my hand did my heart settle. Unexpectedly, a piranha shot up from the water, opening its mouth lined with saw-like teeth, and delivered a vicious bite to the back of my hand while I was mid-air.

A piece of flesh was instantly ripped from the back of my hand. The pain caused my whole body to convulse, and I nearly fell into the river. Despite the agonizing injury, I held onto the backpack for dear life. Several more piranhas exhibited their spectacular leaping ability, jumping from the water trying to bite me. Suspended in the air, and weighed down by the heavy pack, I couldn't evade them.

It was only because Fatty and Shirley Yang hauled me back from behind that I narrowly escaped being torn to shreds by the horde of fish. I wiped the cold sweat from my brow and examined my left hand. Fortunately, the injury wasn't severe—just a patch of skin and flesh torn away. Though the blood flowed ceaselessly, at least bone and sinew were intact.

Shirley Yang rushed to take out medicine to bandage it. “You were too reckless. What’s more important, your life or your gear? If the gear is lost, the Mò Chén Pearl can just stay in King Xian’s Tomb a few days longer, but losing your life is no joke.”

I said to Shirley Yang and Fatty, “What’s a little scratch like this? If I don’t show off some of Hu’s competence today, that American consulting team will start calling us useless again. Right, Fatty?”

Fatty laughed, “Old Hu, what kind of skill is that? Trying to steal a chicken only to lose the rice—you got bitten by a fish yourself! We’ll hold the rear guard. Wait until we get inside King Xian’s Tomb, then you’ll see Fatty’s true ability. I’ll open your eyes and show you what it means when there’s always a higher mountain.”

Shirley Yang first used Yunnan Baiyao to stop the bleeding on the back of my hand, then covered it with hemostatic glue, and finally wrapped the wound with waterproof tape to prevent infection from water exposure. Afterwards, she insisted on giving me a shot of penicillin.

I waved my hands frantically. “No, no, I don’t leave the line for a minor injury, and I’m a bit afraid of needles. Besides, we didn’t bring much of this antibiotic; we should save it.”

Shirley Yang didn’t listen to a word. She told Fatty to pin me to the ground, forcibly administered the injection, and only then did she relent. Given the complex and unknown dangers within this mountain cave, we skipped any rest. After taking a bearing and confirming that the edge of the river channel was barely passable, we slung our packs and prepared to move into Section 11, proceeding along this underground canal out of the riverbed.

We walked along the edge of the channel, observing the impressive scale of this waterway excavated for the construction of the royal tomb. We had initially assumed that King Xian, a mere regional ruler who broke away from the ancient Dian Kingdom, would have a modest tomb. However, judging solely by the canal carved through the mountain, that King Xian, who excelled in the arts of Voodoo and Thug sorcery, must have possessed immense power and influence; the scale of his tomb, built within the Dragon's Vortex, should far exceed our expectations.

We walked deeper into the darkness of the mountain, trekking for nearly another hour, when the riverbank suddenly gave way to a collapse. Every step on the loose rubble sent stones sliding into the water, making it impossible to proceed. It seemed this path was blocked, forcing us to find another natural cave to pass through. After walking a short distance, we heard the roar of rushing water coming from the opposite side of the rock wall, but despite hearing the current, there was no visible path around. We swept our "wolf eyes" (headlamps) around to search for a way; this area was a karst landscape of naturally dissolved rock formations, riddled with large and small holes in the massive rock masses.

After much effort, we found a narrow aperture just large enough for one person to squeeze through. We used the climbing rope to drag our backpacks behind us and wriggled through one by one. Finally, we reached a massive underground waterfall. We had emerged from the rock crevice directly beneath the cascade. Another stream joined the river channel beneath the waterfall from the opposite side. Following the direction of the current, we could see a distant glimmer of light—it seemed the exit was over there.

Shirley Yang said to me, “This tributary system feeding the waterfall must be the route locals discovered during their stone quarrying. Looking at the riverbed topography here, it can’t be more than a few decades old. This looks like it formed recently; otherwise, with this water route available, they wouldn’t have bothered carving the canal through Shalong Mountain to build King Xian’s tomb.”

I replied to her, “This kind of accumulated dust dissolution karst topography is formed by years of water erosion. I learned a bit about it when I was an engineer in the military. In places like this, the entire base of the mountain has been riddled like a sieve by the countless tributaries of the Nujiang River. Some sections have water depths exceeding several hundred meters, and river diversion within caves is a common occurrence; the water just flows lower and lower, and every time a section of rock collapses, a new tributary forms. If this continues, Shalong Mountain will eventually collapse.”

The three of us walked and talked, heading toward the place where the light shone. Halfway there, we noticed a series of caves arranged quite orderly high up on the cliff face, looking very much like artificial excavations. Below the cliff face were distinct stone steps, and scattered on the ground were occasional rotting human skeletons, along with rusted armor and weapons, all decayed beyond recognition.

The scene here perfectly matched the description given by the innkeeper at the Cloudy Inn previously—it must have been a hideout for rebels fighting government troops back in the day. The regions around Dali in Yunnan and the Nujiang River often saw such conflicts starting from the Yuan Dynasty. Because items were difficult to preserve in the damp environment, nearly everything had rotted beyond recognition, making it hard to pinpoint the exact dynasty. Judging by the degree of skeletal decay and the style of the weapons and armor, we could only surmise it might date to the early Qing period.

We always travel on foot when exploring tombs; we don't shy away from arduous treks and value the ability to move freely. Although we abandoned the boat below Shalong Mountain and carried heavy gear on our backs, we hadn't felt exhausted. However, having endured so much peril on this journey, we all wanted to exit the cave as quickly as possible. Thus, we ignored those relics and hurried on.

We followed the water flow to its end, where the river continued forward but flowed underground. This section of the cave was lower than the surface ground outside, meaning this great underground river was invisible from the exterior. We climbed up a sloping pile of rock debris, which bore clear signs of recent flooding. It seemed the large-scale rainfall across the country a while ago had significantly affected the many caves within Shalong Mountain. In the middle of the scree slope, our eyes suddenly caught sight of a cave opening clearly washed out by water. The water had receded now, and in daylight, this exit would be easy to find using the sunlight from outside. The stones here were clearly artificially blocked; without the mountain flood, opening it would have required immense human effort.

We put on our sunglasses and squeezed out of the cave, finally succeeding in passing through Shalong Mountain. Once outside, we looked back: we were situated directly beneath the towering, precipitous cliffs of Shalong Mountain. At the highest point above us, the clouds were thick, while the mountain's outer shell was dark green granite, mottled with lichen, and countless vines and broad-leafed plants grew across the cliff face—an expanse of green that would make finding this small aperture from the outside extremely difficult.

Looking ahead, we saw only towering mountains all around, while the terrain in the center gradually sloped downward, covered by vast tracts of primeval forest. The trees were dense and ancient, the vegetation incredibly lush. The canopies of old trees blocked the sun and sky, featuring many exotic flowers and strange woods whose names we couldn't even guess. Scattered within this expanse were countless ravines, deep valleys, rapid streams, and treacherous fords. Some deep valleys, clear in the sunlight, revealed every blade of grass and flower within, yet the further we looked, the more unfathomable they seemed, a profound, dizzying depth. Other areas were shrouded in mist and cloud, presenting a hazy, mysterious vista.

This was a primitive land, isolated from the world, cut off by snow-capped mountains and great rivers, lying between the Nu River and the Lancang River. I took out the human-skin map to confirm the route into the Insect Valley.

Fatty raised the binoculars to look down at the jungle. After observing for a moment, he suddenly grabbed my arm and thrust the binoculars into my hand. “Stop looking at the map! Look over there—do you see all those giant golden butterflies? That valley has to be right there.”