Jia Zhuangyuan nodded gravely and said, "Yes, that is what I believe. This object now convinces me even more strongly of the legend's truth. This water monster is the guardian of the entrance to the Boundless Demon Treasury."

Liu Dashao then asked, "Senior Jia, why didn't you say so earlier? When I asked if there were any fish in the lake, why didn't you tell everyone then?"

Jia Zhuangyuan gave a wry smile. "Legends are just legends, and I couldn't be certain. Besides, if we hadn't found any trace of human activity on the lake surface, we might have had to look elsewhere. Why would I mention it and add to everyone's mental stress? Exploring the lake is, after all, a dangerous venture; who knows what that water monster is."

He then looked up at everyone and continued seriously, "It’s different now. Based on my twenty years of tomb-seeking experience, my intuition tells me the entrance to the Boundless Demon Treasury must be at the bottom of this lake. Even with a water monster, we must go down to investigate. Frankly, this volcanic lake has existed for perhaps thousands of years; it’s impossible for there to be no fish life here. There must be a reason for the tranquility. I believe the presence of the water monster is what suppresses the proliferation and numbers of the lake's inhabitants."

Fan Debiao asked, confused, "Senior means the water monster devoured a large number of the lake's creatures, resulting in the calm surface?"

Jia Zhuangyuan nodded and said no more. Everyone else fell silent too.

It seemed descending into the lake was inevitable, yet no one knew what the water monster was or where it might be lurking. Staring at the placid water, a chill crept up Liu Dashao’s spine, as if a pair of eyes were peering at them from the depths of the blue lake.

After sitting in silence on the rocks for a while, Liu Dashao suddenly looked up and asked Jia Zhuangyuan, "Senior Jia, since you mentioned ancient texts record a water monster emerging from the Ying Mountain Volcanic Lake, did they give any description of its general appearance?"

Jia shook his head expressionlessly. "The records in the ancient texts are vague, only mentioning that during those years, people saw large monstrous beasts appearing in the water—huge and pitch-black. That was all."

"How can one guess based only on 'huge and pitch-black'?" Fan Debiao commented.

Jia Zhuangyuan suddenly stood up and addressed them. "For both public and private reasons, I wish to attempt the dive myself. You all may wait on the shore."

With that, he took off his backpack, pulled out an item resembling black leather clothing, stripped off his outer jacket, and put on the black leather garment. As he finished dressing, he saw their astonished gazes and chuckled. "This is the legendary 'Water Suit.' And look what I have now?" Saying this, he took out two things from his backpack—items as thick as chopsticks, resembling long, stout needles. Pang Xiaotai exclaimed, "I know! Those are the Water-Splitting Thorns!"

Jia Zhuangyuan nodded with a smile. "Correct, these are the Water-Splitting Thorns. A friend gave me this gear over a decade ago. For those of us in this line of work—climbing mountains, entering water, digging tunnels, burrowing into the earth—only professional tools make the work twice as effective."

A moment later, he turned serious and told them, "There is definitely a profound mystery hidden in this lake water. When I go down shortly, you all must be extremely vigilant. If I don't resurface within twenty minutes, it means something has likely happened to me." He then quickly glanced at Liu Dashao again.

Liu Dashao stared intently at the calm lake and said slowly, "Senior Jia, we know nothing about the situation beneath this lake. Going down alone like this is too reckless, isn't it?"

The others began speaking up one after another, all conveying the same sentiment: they needed to approach the dive cautiously and avoid unnecessary danger.

Jia Zhuangyuan frowned and shouted, "Stop talking! If I don't go down to investigate, what do you suggest we do? No one knows the specifics of what’s in the lake; only by going down can we find out. I feel I have been through similar situations before, and my water skills and experience are top-tier. I decided to go down myself because I fear you impulsive youngsters might rush in without knowing the depth and face danger. And look at you now—do you think this old man lacks the ability?"

Everyone quickly stammered denials. Liu Dashao gestured for them to be quiet. He then walked up to Jia Zhuangyuan and said, "Senior Jia, we all know your good intentions; in fact, we are concerned about you. Going down alone is genuinely risky; if you discover anything or encounter danger, there is no one there to look out for you."

Jia Zhuangyuan blinked his small eyes and smiled at Liu Dashao. "I can hold my breath underwater for twenty minutes and dive a hundred meters. Which of these young whelps can do that? And who would dare accompany me on this journey?"

Liu Dashao was momentarily speechless.

Just then, Cai Qingchong suddenly stood up and said to Jia Zhuangyuan, "Senior Jia, I wonder if you have another Water Suit? I am willing to accompany you into the lake for a look. While my underwater skills may not match yours, I can certainly assist you."

Jia Zhuangyuan stared at Jiao Yiming in surprise, unable to speak for a long moment. Everyone else was also astonished; it turned out Cai Qingchong possessed such excellent underwater capabilities.

Jia Zhuangyuan studied Cai Qingchong for a while, then turned back to his backpack and retrieved another set of the Water Suit, handing it to Cai Qingchong. He then said, "I do have two of these Water Suits, but I only have this one pair of Water-Splitting Thorns." He paused, his expression seeming hesitant, then added, "No, you take the Water-Splitting Thorns; I will use my dagger."

Cai Qingchong, while taking off his outer jacket, smiled at Jia Zhuangyuan and said, "Senior Jia, I have my own weapons for use underwater; you don't need to worry. As for the Water-Splitting Thorns, you should keep them."

After Cai Qingchong had also put on his Water Suit, everyone stood up and began to chatter, urging Cai Qingchong and Jia Zhuangyuan to be careful once they entered the water. They advised them first to gauge the general layout of the lake, and if they could find clues, that would be best; if not, they must immediately return upon encountering the water monster.

Jia Zhuangyuan finally grew impatient and declared, "What are you all doing? Am I, Old Jia, so advanced in years that I need reminders from you juniors?"

He then took Cai Qingchong by the arm and walked toward the lake. The others exchanged helpless smiles; indeed, Old Jia’s age came with a temper that sometimes left them at a loss for words.

Everyone watched the two men walk to the lakeside, then slowly wade into the water. As spray splashed, the two disappeared from sight. Ripples spread out from where they entered the water, fading gradually until the entire surface returned to its original stillness.

The others turned away. Yang Weidong asked with a hint of worry, "Do you think they will encounter that water monster?"

Fan Debiao spat out, "Don't speak ill omens, kid. Could that water monster have survived for several millennia? Perhaps it died long ago, its remains dissolved into the mud at the bottom. Bug and Senior Jia will surely emerge safely from the water with good news."

Yang Weidong gave an awkward chuckle and stared at the spot where Jia Zhuangyuan and Cai Qingchong had entered, offering no further argument.

Everyone quieted down, gazing at the lake. In truth, everyone harbored worry for Cai Qingchong and Jia Zhuangyuan, but no one wished to voice it, silently praying that the two would successfully find clues to the entrance and return safely to the shore.

Ten minutes passed, and the lake remained placid. Everyone grew anxious, craning their necks, eyes fixed on the mysterious blue water. Fan Debiao even stood up and paced restlessly by the shore.

Another five minutes elapsed; Jia Zhuangyuan and Cai Qingchong had been underwater for a full fifteen minutes. Everyone’s heart began to pound nervously. Liu Dashao involuntarily stood up and slowly walked toward the lakeside, his hand seemingly sweating. Everyone followed his lead, moving forward.

Just as the group reached a spot only a few meters from the water's edge, the entire lake surface suddenly rippled. In the instant everyone paused, a thunderous "BANG!" erupted about twenty meters directly ahead of them, and a long, dark object shot out of the water, accompanied by a roar that echoed throughout the entire crater. A shiver ran through the group—their worst fears had come true. The legendary water monster had finally revealed itself.

When everyone got a clear look at the creature, its appearance was almost beyond belief! Surely, they had all seen dinosaurs in science fiction movies? The part of the monster visible above the water bore a striking resemblance to the Elasmosaurus from Jurassic Park.

The group quickly retreated toward the shore. The Plesiosaur, now apparently furious, was swimming rapidly toward them, seemingly pursuing something. Fan Debiao, with keen eyes, shouted, "Senior Jia and Bug are right ahead of it, swimming toward us!"

Liu Dashao immediately yelled, "Yang Weidong, open fire! Cover them!" Before his words had faded, the Type 56 submachine guns held by Fan Debiao and Yang Weidong erupted in fire. Bullets whistled past, pouring toward the Plesiosaur-like creature. It seemed completely unprepared for such an attack. The bullets struck the part of its body exposed above the water.

Its flesh began to show bullet holes under the impact, and red blood oozed out, quickly staining the surrounding water crimson. It let out a piercing shriek, shaking its long neck and relatively small head, and stopped pursuing Cai Qingchong and Jia Zhuangyuan, sinking rapidly back into the water. The massive splash generated by its retreat sent water flying onto the onlookers ashore.

The group rushed to look and saw that fortunately, Jia Zhuangyuan and Cai Qingchong were less than ten meters from the shore. Holding their weapons, the others swiftly waded into the shallow water, keeping watch on the lake while helping the two struggle ashore.

Jia Zhuangyuan and Cai Qingchong lay sprawled on the rocks by the water, panting heavily and coughing incessantly. It seemed the water monster had chased them from beneath the surface all the way to the shallows, exhausting them thoroughly.

A few minutes later, Cai Qingchong finally managed to curse, "Damn it, that water monster is truly huge, and it’s fast in the water. I almost became its snack."

Fan Debiao asked, still shaken, "What was that thing?"

Liu Dashao said, "It looked remarkably like the Plesiosaur that lived in the water during the age of dinosaurs. Could it be that this creature never went extinct? But these things are supposed to be gentle in temperament. Why is this one in the volcanic lake so ferocious?"

Jia Zhuangyuan retorted gruffly, "You know nothing! It is indeed a Plesiosaur, but this particular specimen is viciously aggressive!"

Jia Zhuangyuan’s words surprised everyone. What exactly was a Plesiosaur? They recalled barely seeing anything like it in the dinosaur movies.

Jia Zhuangyuan then warned them, "Let's move further away from the shore. Now that we’ve injured this thing, it will surely hold a grudge. Be careful it doesn't sneak up to the bank and snatch one of us unlucky fools for a snack before we know it—that would be disastrous."

Hearing this, the others shuddered and quickly helped the exhausted Jia Zhuangyuan and Cai Qingchong away from the water’s edge, heading back.

After walking only about ten meters, just as Jia Zhuangyuan predicted, the water behind them suddenly erupted with a loud "BANG!" The water monster surfaced not far from the shore, unleashing a deafening roar directed at the fleeing group.

It was then that Liu Dashao noticed the creature’s head and mouth formed a streamlined, inverted triangle, the head being relatively small, but the mouth enormous, revealing rows of long, sharp, interlocking teeth resembling spikes. It looked incomparably savage.

Seeing them flee the shore, it grew enraged, churning its neck and head in the water, constantly roaring its fury. The hundred-meter expanse of the lake seemed to be turned upside down by its thrashing.

Reaching the rock where they had first found the traces of human activity, Jia Zhuangyuan said, "You can put me down here. Let me rest for a while."

They quickly set him and Cai Qingchong down. Then, turning back, they watched the roaring monster in the water with pounding hearts. It was a blessing that both men were strong swimmers and relatively lucky; had they reached the shore any later, the consequences would have been unimaginable.

Cai Qingchong was still gasping for air, leaning against the rock, and pointing at the Plesiosaur in the water as he cursed, "You son of a bitch, keep chasing me if you dare! Showing off in the water—what kind of hero are you!"

His outburst made everyone smile slightly. After all, the Plesiosaur was just an animal; how could it be called a hero? Nevertheless, his words significantly diluted the terror that had gripped them.

After about ten minutes, the Plesiosaur in the lake seemed to realize the group would not approach the water again. It appeared tired from its agitation and dared not leave the lake to pursue them. Finally, it circled the water listlessly for a while before slowly submerging.

Only then did the others turn away from the lake and remember to ask Jia Zhuangyuan and Cai Qingchong if they had found any clues underwater.

Jia Zhuangyuan and Cai Qingchong had regained some strength after resting ashore. So, Jia Zhuangyuan propped himself up on the rock and began to recount, "We swam down and followed the line of that man-made rock structure straight to the bottom. The structure of the lakebed is very strange—a funnel-shaped slope, and this artificial rock band extended down along that slope to the bottom. When we reached about a hundred meters underwater, we saw a strange stone carving, resembling some ancient demon race, embedded in the underwater rock. Just as Cai Qingchong and I were about to examine it closely and guess its purpose, the water monster appeared. At that moment, I felt a sudden chill on my back, likely caused by the underwater current stirred up by a large aquatic creature approaching. Without even looking back, I knew the water monster was there, so I yanked him and we fled back. The rest, you already know—that bastard chased us relentlessly, as if we had raided its nest. Several times, if I hadn't executed sharp underwater turns, I would have been eaten as a snack."

After Jia Zhuangyuan finished, Liu Dashao asked, "Senior Jia, what do you think that strange demon carving might be?"

Jia Zhuangyuan pondered for a moment. "Perhaps it's a directional clue, or maybe a switch to activate a mechanism. I spotted it only moments before the Plesiosaur caught up; I didn't have time to look closely or interact with it."

Liu Dashao nodded. "The fact that this rock band extends that deep, including that demon marker, confirms Senior Jia's judgment. The entrance to the Boundless Demon Treasury might indeed be within this volcanic lake. However, we first need to figure out how to deal with this Plesiosaur."

Jia Zhuangyuan shook his head, looking dejected. "That's right. But this creature was the overlord of the water tens of millions of years ago. In the water, its speed is terrifyingly fast, and it’s exceptionally fierce. Dealing with it will be extremely difficult, I estimate."

Seeing Jia Zhuangyuan’s crestfallen expression, the others also realized how thorny the Plesiosaur problem was. Liu Dashao looked at their helpless faces, sighed softly, and said, "Let’s rest here for a while. There will be a way. While we rest, everyone think about it."

So, they sat on the ground, took out food and water, and began to rest.

A little over ten minutes later, they had quenched their thirst and hunger in silence. Jia Zhuangyuan even pulled out a long, black iron pipe-stemmed tobacco pipe from his backpack, packed it with tobacco, and began smoking. From entering the Ge Ge Ruins to the bronze Buddha statue and now, this was the first time they could rest without immediate danger.

The issue of the water monster was raised again through everyone's chatter, but they couldn't devise a plan to counter it. After all, once in the water, their guns became useless, and in that realm, the Plesiosaur reigned supreme for tens of millions of years; in terms of speed and strength, none of them were a match. What could they do?

Jia Zhuangyuan listened silently to the discussion without offering any commentary. Soon, everyone fell silent again, unable to conceive of a way to deal with the massive creature in the water.

At that moment, Jia Zhuangyuan tapped out his pipe. He spoke slowly, "For now, our only option is to find a way to attract the Plesiosaur's attention, or lure it out of the water so we can shoot it down."

Hearing his words, everyone turned their gaze toward Jia Zhuangyuan, looking at him with renewed hope that he might present a feasible plan.

Jia Zhuangyuan blinked his small eyes, looking somewhat smug, and then continued, "These things were the overlords of this planet tens of millions of years ago, but their weaknesses were also very clear: their intelligence was rather low, and almost every action they took was based purely on instinct. We can exploit this, either by drawing its attention or luring it out for execution. I think killing it is the only way to be truly safe."

Fan Debiao then interjected, "But this thing absolutely won't leave the lake water. How can we kill it? It was injured by our guns just now; if it gets shot again, I estimate it will never show its head above the surface again."

Everyone nodded in agreement with his assessment. Even if this creature was dim-witted, it knew what had wounded it. If it were injured twice, it would likely never reappear above the surface.