His muttering echoed in the tunnel. Immediately afterward, he heard a sound that wasn't his own.

Rumble, rumble.

Like countless bricks rubbing against each other, creating an infinite amount of stone dust.

Li Ang's expression changed drastically. He turned his head to look and saw a faint light flickering at the end of the tunnel, projecting a massive figure onto the stone wall.

He had already memorized the topographical map of the entire tunnel. The sound was coming from…

The stone wall next to the f room!

Li Ang made a decisive decision, dimming the kerosene lamp to its lowest setting and using his hand to shield the light.

He gripped the screwdriver,

hunched over, lightened his footsteps, and silently sprinted along the wall toward the end of the tunnel.

When he rushed out of the corner,

he saw the bricks on the wall next to the f room rapidly rearranging themselves.

Through the two palm-width gaps in the stone wall,

he could vaguely see a figure wearing the same rubber suit as him, carrying a lantern,

slowly walking toward a white-haired woman standing at the edge of the tunnel, wearing a gorgeous gothic black dress and a white blindfold.

"Wait!"

Li Ang strode forward and shouted loudly,

but with a "boom," the stone wall completely closed, leaving not a single crack.

"..."

Li Ang stood in front of the stone wall, holding the lamp, panting heavily.

Running that stretch of road had left him breathless, every limb feeling as numb and sore as a squeezed-out sugarcane.

But what concerned him even more was the rubber-suited figure that disappeared behind the stone wall, and the white-haired woman who was waiting behind the stone wall.

"What exactly is going on… Why is that person wearing the same clothes as me? Is he a participant like me, or is he the dungeon designer himself…"

The tunnel gradually returned to darkness. Li Ang, leaning against the wall and muttering to himself, realized that

the kerosene lamp, set to its lowest setting, had quietly gone out during the running.

Li Ang subconsciously reached for the envelope.

But when his fingers touched the matchbox he had hidden inside the envelope, his hand movements paused inexplicably.

"There are only two matches in the B room's matchbox. Could it be that the dungeon designer knew that I would lower the light and chase after them, causing the kerosene lamp to go out…"

Li Ang pursed his lips, struck a match, and relit the kerosene lamp.

Under the lamplight, he re-examined the stone wall.

He had already checked before. There were no hidden bricks on the wall, and it wouldn't react to passwords like "Open Sesame."

"The cylindrical groove seemed to have been used just now… There are residual water stains in it…"

Li Ang reached out and wiped the groove on the stone wall. After hesitating for a moment, he put his glove to his mouth and licked the fingertip of the glove.

"A little sweet… and a bit metallic? Could it be…"

Li Ang's expression changed slightly.

He wiped his glove with the remaining scrap of cloth, glanced at the stone wall,

then turned and left, returning to the front of the C room door.

"If I hadn't cracked the password on the C door before,

then now, I should have to install the kerosene lamp in the dark and decipher the password by comparing it to the letter.

Now that I already know the password is to have light, combined with the completely dark scene in this tunnel, it means I should use the kerosene lamp now…"

Li Ang muttered to himself, holding up the kerosene lamp and bringing it closer to the eye pattern on the C room door.

The light illuminated the pattern, but nothing happened.

"Huh? No reaction?"

He frowned, reached out to rotate the knob, adjusted the length of the wick, and gradually increased the brightness of the light.

Finally, when the light reached a certain threshold, the metal door began to slide to the right.

Like the B room, there were two doors in the C room.

He stood in the center of the circle, waited for the inner door to open, stepped inside, and the inner door closed simultaneously.

Perhaps to synchronize with the tunnel, there was no light in the room.

Li Ang cautiously moved forward, holding the kerosene lamp,

and discovered that the C room was empty.

There was a large red button on the wall.

Three items were placed on the floor:

a gold-rimmed water glass, with the characters "5L" engraved on the bottom of the cup,

a plastic pipe with a diameter of five centimeters, and a letter.

Like before, he opened the envelope. The contents of the letter were:

"Aha, Morgan, you've successfully arrived at the third room!

Should I congratulate you on your good progress, or condemn you for being too slow?

Considering that you barely cracked my code (although it was really simple), I'll be merciful and give you some hints.

The button on the wall is connected to the water supply system in the entire tunnel.

You must press the button to open the inner door of the C room and start the water supply system for 5 minutes.

You'll need some additional operations to get the water to the d room door – you know how to do it.

Finally, a reminder to listen carefully."

Almost the instant Li Ang finished reading the last word, the sound of a door opening came from above the ceiling.

The sound of a man's leather shoes and a woman's high heels, one after the other, arrived at the center of the ceiling.

"Failed, failed."

The man's distracted voice rang out, "Failed, failed, failed..."

"Father, please cheer up."

A clear, beautiful female voice rang out, more tender than the woman's voice he had heard in the B room. "Mother and little sister need you to save them.

If even you give up, then there will be no one in this world who can save them."

"Save..."

The man's voice sounded like a dream. "I've tried all the methods, but I still can't make the correct potion...

I need more time… time…"

After a long silence, the man spoke again, "Alice."

"I'm here."

"The time now."

"9:30 PM on the 7th."

"Is there still time?"

"Are you talking about that? There's still time."

"...I'm going to go down into the well."

"Is that so? I'll go prepare right away."

"You don't have to come..."

"What silly things are you saying? If I'm not there, you'll definitely make a mess of the lab, and you won't even remember where the test tubes and beakers are."

"...Thank you."

The sound of footsteps faded away amidst Li Ang's shouts.

"It's like before again."

Li Ang took a deep breath. "Okay, this time a female voice appeared again.

For now, I can assume she's the alchemist's eldest daughter.

She said it's 9:30 PM on the 7th. Judging from the battery consumption on my left arm, I should have woken up at 9:00 PM on the 7th,

left the A room at 9:10 PM,

entered the B room at 9:15 PM, and heard the couple's conversation upstairs.

Wait, the alchemist and his wife were just discussing what to do after the problem was solved.

How could he have decided that he had already failed after only 15 minutes?

He also said he was going down into the well to save his wife and youngest daughter…"