117: Sinking Sea Formation and Underwater Door

"Coffin Pond?" Upon hearing the name, Wang Dalong immediately broke out in goosebumps. He cautiously peered underwater, but saw nothing except darkness. It was a profound depth that seemed to swallow all light, as if leading straight to hell.

"Just how deep... is it down there?" he whispered.

"I don't know." Uncle De shook his head and pulled a crumpled cigarette from his pocket to light it, his hands trembling slightly. "People tried to find the bottom with long ropes before; they let out hundreds of meters and still didn't reach it. It's like a bottomless pit."

Wang Dalong sucked in a breath of cold air.

Lin Feng ignored their conversation. From his backpack, he took out a palm-sized black device—a Portable Underwater Sonar Detector. This was one of the "black technologies" he had exchanged for using system prestige; it could penetrate murky water and accurately map out 3D terrain within three hundred meters underwater.

He connected the detector to a drone and then controlled the drone to slowly rise and hover directly over the bay.

“Buzz—”

The detector started up, and ripples of invisible sound waves spread beneath the black surface of the water like pebbles thrown into a pond.

Wang Dalong leaned over to Lin Feng's tablet. On the screen, the underwater scene was being scanned and constructed bit by bit.

Initially, it was a steep cliff wall, plunging vertically.

Ten meters, twenty meters, fifty meters... The depth continued to increase, but there was nothing besides the rock wall.

"There's nothing there, Brother Feng," Wang Dalong said with some disappointment. "Is it really just a bottomless pit?"

Lin Feng didn't speak; he simply turned the detector's power to the maximum.

Depth: one hundred meters.

Just then, the 3D model on the screen changed!

It was no longer just a rock wall. At a depth of one hundred meters underwater, some extremely regular objects appeared that could not possibly be natural formations!

They were giant stone pillars!

As the drone moved through the air and the scanning range expanded, the full view of the underwater scene gradually appeared before their eyes.

Wang Dalong's breathing stopped.

Uncle De's eyes also widened, and he didn't even notice when the cigarette in his mouth fell into the water.

At the bottom of the bay, a massive array composed of hundreds of giant stone pillars stood silently. Each of these pillars was over ten meters high and several meters thick, arranged according to some mysterious pattern. Looking down from above, the entire array formed a huge shape resembling a Bagua!

And in the center of the array was an even larger circular stone platform. In the middle of the platform was a bottomless black hole.

"Oh... my... god..." Wang Dalong's voice was trembling as he pointed at the screen, looking as if he had seen the most incredible miracle in the world. "What... what is this? Was it built by underwater people?!"

"It's a formation," Lin Feng's gaze was more focused than ever before. "A lock."

He finally understood.

The strange "dragon vein waters" in this sea area were not a natural phenomenon at all!

It was this giant stone array submerged a hundred meters deep that disrupted the ocean currents. Like a massive water pump, it used the power of the tides to create chaotic undercurrents outside the bay, preventing any ships from approaching.

It was a lock—an incredibly massive lock that used the entire ocean as its power source!

And the "dock" hiding the final fleet of the Southern Song Dynasty was right behind this lock!

"Then... where is the entrance?" Wang Dalong asked urgently.

Lin Feng pointed to the hole on the circular stone platform in the center of the screen. "There. That is the 'Water Gate'."

"Over a hundred meters deep! How are we supposed to get down there?!" Wang Dalong was dumbfounded. "We don't even have oxygen tanks! Going down is just a death wish!"

It was almost an unsolvable deadlock. They had found the place, but they couldn't get in.

Just then, the system's notification sound rang in Lin Feng's mind once again.

[Key formation node detected: Tidal Lock.]

[Analyzing formation operation patterns... Analysis complete.]

[This formation utilizes lunar gravity and local tidal resonance to form a periodically opening energy circuit. During the intervals of the energy circuit transition, the 'Water Gate' at the center of the formation will generate a brief, stable vortex channel.]

Immediately following that, a virtual countdown was projected directly onto Lin Feng's retina.

[Next 'Water Gate' opening window: 2 hours, 14 minutes, 32 seconds.]

Lin Feng's heart skipped a beat.

There would only be one chance. And it was just two hours away.

He turned to look at Wang Dalong, then at Uncle De, who was still completely stunned.

"Fatty," his voice was very calm, "get out the basic diving gear we brought."

They had only brought the simplest snorkeling masks, snorkels, and fins in their backpacks; it wasn't deep-sea diving equipment at all.

Wang Dalong froze. He looked into Lin Feng's eyes and instantly understood something, his face turning deathly pale.

"Feng... Brother Feng... don't scare me!" His voice carried a hint of crying. "You don't mean... you're going down there by yourself when that 'Water Gate' thing opens, do you?"

Lin Feng didn't answer; he just silently took a waterproof tactical headlamp from his bag and began checking the batteries.

His actions were the best answer.

Wang Dalong grabbed his arm, so anxious that he was almost in tears. "No! Absolutely not! This is over a hundred meters deep! It's not a swimming pool! You'll die if you go down! The water pressure alone will crush you into a meat patty!"

"I must go down." Lin Feng looked up at him, his eyes showing no madness, only an unquestionable calmness.

"In those memories, they mentioned 'opening the Water Gate.' That means the passage is passable at specific times."

He looked at the deep hole on the tablet and said word by word.

"Zhang Shijie and his men could enter. So can I."