Underground Pipe Network Layer

Regarding the reverse surge of energy.

For a moment, neither Lu Yuan nor Bolen had any good ideas.

For now, we can only observe.

The sixth night came quickly.

The light from the Wall Runes dimmed a little more.

And tonight, the Ghoul will attack again.

Fortunately, the number is not large.

Only a few individuals emerged from the direction of the cave entrance and crawled towards the position along the area covered by the fungus.

They were all Ghoul in a state of Absolute Hunger, emaciated, with their ribs clearly visible, and their eyes filled with a thirst for Flesh.

Boer and his men easily resolved the issue.

A dozen or so.

It didn't take much effort.

But this was not a good start. After two consecutive nights of silence, the forces from the Abyss were resuming their probing attacks.

Although it was just a small "tentacle" being extended to check if the Defense Line here were still intact.

Lu Yuan stood at the second-floor window, watching Boer's men drag the Ghoul remains onto the bronze surface and wait for them to corrode on their own.

Occasionally, sporadic gunfire could be heard from other positions in the distance, but it quickly subsided again.

Bolen was on site, checking the Gray-Green Backflow every two hours.

The grayish-green substance flowed steadily along the section of Copper Pipe he had repaired, maintaining its direction and concentration.

And there was almost no fluctuation.

Both the concentration and the flow rate are almost identical.

It was as if it were being precisely controlled by something.

Bolen began to frown after the third test.

This shouldn't be the pattern of natural Contamination backflow.

The things on the other side of the Abyss are so chaotic; logically, they should be surging like the tides.

However, the Contamination inside the Copper Pipe was far too uniform.

If it weren't for the fact that this section of pipe was repaired this time...

Now Glock has entered the inner city with these two pieces of information, hoping to find some clues.

The horizon began to turn white.

Footsteps came from the side.

It's Bolen.

"Come and see, this seems like good news." Bolen gestured for Lu Yuan to come over.

"Oh?"

Lu Yuan walked over and squatted down.

Bolen's fingers were slowly sliding along the surface of the Copper Pipe.

"When I was repairing this section of pipe yesterday, I only noticed the corrosion on the inner wall and that the Copper Plate had been touched."

He stopped pointing, his fingertip touching a tiny protrusion on the tube wall.

"But during last night's monitoring, I discovered a problem."

He glanced at Lu Yuan.

"The Contamination is too stable."

Lu Yuan frowned.

"Tested every two hours, and the results were almost identical six times." Bolen's voice was very low.

"Have you ever seen anything like this? The Contamination underground couldn't possibly be this even, unless..."

"Unless the source isn't in that underground place, or something is controlling it."

"Yes." Bolen nodded. "That's why I thought about it a bit more last night."

He tapped along the protrusion with his fingers.

"Then I thought, maybe I've made a mistake, maybe the Copper Pipe itself is faulty."

Lu Yuan leaned closer to take a look.

Lu Yuan couldn't discern anything from the yellowish-black Copper Pipe.

"What's wrong?"

"These were all replaced later," Bolen said in a low voice.

He drew two lines on the ground with his cane.

"The original Conduction Network in the city wall was laid along with the city during its construction. Made of bronze, the Inscription share the same style as the wall itself, and every stroke was hand-carved."

He pointed to the Copper Pipe at his feet.

"But this pipe clearly doesn't fit."

He looked up.

"Someone dismantled this section of the original structure and replaced it with one they cast themselves."

Lu Yuan's gaze darkened.

"Couldn't it be for repairs? Otherwise... what's the direction?"

Bolen stood up and tapped the pipe wall with his cane.

"This is the second reason I called you here."

He squatted back down, placed his palm on the tube wall, and slowly moved it along the direction.

"I've studied the Inscription on the Bronze City carefully; their orientation is easy to guess, but this one is different."

His finger stopped at the bend in the pipe.

"It veered downwards, extending underground, not connecting to the Outer City, but heading in some underground direction."

Lu Yuan was taken aback.

Where do you think this pipe leads?

Bolen paused for two seconds, then stood up and dusted the rust off his hands.

"I don't know, but it definitely can't be that the Abyss underground."

He turned around and looked into the distance.

"Think about it, last time we went down into the Abyss, we saw Copper Pillar that were at the foundation level, with Inscription even older than those on the city walls. Those things were definitely built along with this city."

"I'll continue, "Bolen said.

"With that level of Inscription and copper concentration, the sealed object would be absolutely catastrophic."

"Even if it's just overflowing, Copper Pipe of this thickness definitely can't withstand it."

"Unless..."

Lu Yuan understood what Bolen meant.

"Unless they didn't come directly from the Abyss."

"Yes." Bolen nodded.

"The end of this pipe is most likely not in the Abyss, but somewhere underground, where there is a Source of Pollution."

He tapped the ground with his cane, then pulled out a roll of parchment from somewhere.

The surface is densely covered with drawings depicting the general layout of the Bronze City.

Bolen pointed to a spot above and continued.

"But if someone creates a new point of Contamination on the seal, such as in the underground Pipe Network Layer of Bronze City, then even the strongest seal will be useless."

"Underground Pipe Network Layer?"

"Yes, there's a Pipe Network underground in Bronze City, containing sewage, rainwater, refuge passages, storage rooms... it's all there."

"And I reckon this pipe is heading in the direction of the underground Pipe Network."

Bolen remained silent for a few seconds.

"I'm going down to check, I'll follow this pipe to trace its path, and once I get to the scene, I'll know immediately."

Lu Yuan glanced at him but said nothing.

After a slight hesitation, Bolen added another sentence.

"I'm very interested in this kind of Contamination that can Contamination copper, and of course the Night Watcher can't just stand by and do nothing."

Upon hearing this, Lu Yuan finally nodded.

"Let's talk about it during the day."

"Clear."

The night passed quickly. After confirming that there were no Ghoul, Lu Yuan instructed Boer to arrange for some of the Night Watcher to maintain patrols around the collapsed area.

As for the rest, they will come with me.

The target was 300 meters behind the collapsed position, behind a half-collapsed stone wall.

There are access ports for underground Pipe Network there.

The cast iron cover plate, less than one meter in diameter, is embedded in a groove in the copper floor.

The cover was covered with a thick layer of Carrion Fungus, the grayish-green fungal layer binding the iron cover and the surrounding Copper Plate together.

Upon seeing this, Lu Yuan felt a sense of foreboding.

Boer sprinkled Copper Powder around the edge of the cover plate.

A hissing sound rang out, and the bacterial layer quickly curled up and fell off.

Kael used a copper crowbar to pry open the cover.

The rusted iron cap made a dull cracking sound, and a damp, cold wind carrying a strange stench rushed up from the cave entrance.

After some time, Lu Yuan finally looked at the vertical shaft.

An iron ladder is embedded in the well wall, extending downwards for four or five meters.

I just glanced down.

[Environmental Perception: A small amount of Source of Pollution detected...]

"By the way, have you informed the Alchemy Workshop about our underground Pipe Network removal?" Lu Yuan turned to look at Boer.

"The notification has been given, Kael Bolen, and two other brothers."

Both of these brothers are veterans.

An old soldier with a stubble beard and missing half of his left little finger, and a nimble young man.

There were six people in total.

Two Sandworm Oil Lamp and four jars of spare oil.

One jar of fire powder, two bottles of Mithril, two jars of Copper Powder, and other items.

"Go, get off."

With Lu Yuan's command...

The crowd filed in.

The shaft is not deep.

It only took a little over four meters to reach the bottom.

The soles of the boots made a dull thud as they stepped on the wet stone bricks.

The Sandworm Oil Lamp was lit, and its pale white light spread out.

Before us was a passageway about two meters wide.

The walls are made of brick and stone on both sides, and the top is a copper arched frame.

Water seeps through the cracks in the stone bricks on the ground, accumulating into a shallow layer.

The air is damp and chilly; your breath condenses into White Mist here.

The first thing Bolen did wasn't to look at the road, but to touch the copper frame on the wall.

"The copper is still conducting electricity here! The situation doesn't seem so bad yet."

At this moment, Boer said:

"The underground Pipe Network is very safe. The City Hall used to have people specifically responsible for its maintenance. Besides, quite a few people live here. And if I remember correctly, there should be a separate lighting system here..."

Boer didn't continue, because as far as he could see, it was pitch black.

There was no sign of the so-called lighting system at all.

At that moment, Lu Yuan was holding up a lantern and looking to both sides.

Every three or four meters along the wall, there is an iron lamp holder, petal-shaped, with a fluorite or oil lamp placed in the center.

But it's all empty now.

Some lamp holders are still embedded in the wall, with only the base remaining.

The upper half was broken off at the waist and lay askew to one side. The broken surfaces of the iron petals were jagged, showing signs of being forcibly broken.

The marks looked very similar to the way the Ghoul broke lampposts on the ground.

"It was the Ghoul who did it," Boer said in a low voice.

Lu Yuan did not respond.

He was looking at something else.

On the left wall of the passage, about one meter above the ground, there is a dark red drag mark.

The drag marks extended from the front, drawing a crooked arc along the wall before disappearing into the shadows at the corner.

It's blood.

Blood that has been there for a long time.

It has dried completely, turning into a dark red, almost black, thin film.

But the shape of the mark says it all.

"Walk."