"In any case, let’s calm down and find the time machine first."

Li Ang nodded, retraced his steps back to Room A, and took a look inside. Nothing had changed.

"If only I could trigger a monster, beat it to a pulp, and have it drop all the room keys directly. It would save me the trouble of searching one by one."

Li Ang knew that what he was saying was impossible. He sighed and resigned himself to returning to the tunnel.

The stone walls next to Rooms A and F were quite sturdy. He chiseled at them with a hexagonal screwdriver.

He couldn't even knock off a shard of brick, let alone scrape off the adhesive between the bricks.

"Based on the number of steps I’ve taken along the wall and the trajectory, this tunnel should be a concentric circle.

Stone wall A next to Room A,

And stone wall B next to Room F,

Are about ten meters apart. For now, I don't know if these two stone walls are connected or separate."

Li Ang muttered to himself as he arrived in front of stone wall B next to Room F. He carefully examined the cylindrical groove on it.

"This shape wants me to put in an energy cell, or something similar in shape, right?

But I tried it before, and I couldn't remove the battery with brute force alone."

Li Ang pondered, "Considering the amount of puzzle-solving in Room A, it's impossible to ask me to open Room A within the first minute of the game, under a strong debuff, and then install the battery into the stone wall.

That is to say,

As the mission progresses, a certain room might provide me with a new, removable battery? Or directly allow me to get rid of the debuff..."

He scratched his head, raised his chin, and shouted toward the tunnel, "Hello?

Dungeon designer, are you there?

I say, can we skip these meaningless steps and go straight to the final duel?

Huh?

Do you dare to fight me? I'll let you know what a real black hand is!"

The provocative voice echoed in the tunnel, but after a long time, there was no response.

Li Ang suspected that some places in the dungeon might have miniature monitoring cameras or recording devices. In order to further test (and also to vent his emotions),

He checked the doors one by one while shouting harsh words such as, "I’ll kill you within three days, and scatter your ashes."

The style of the lock in Room F was different from that of Room A and the clothing he was wearing. It was another key.

Room E had the letters 2f2s21m2m3s13t2 written on it. The combination lock below had six digits and needed to be composed of six of the twenty-four letters.

Li Ang tried words like "aaaaaa", "bbbbbb", "window", "bronze", and "energy" one after another, but the door did not change.

"If 2f2s21m2m3s13t2 is a cipher, then I should also find a corresponding key."

He spread his hands and simply chose to give up, walking to the door of Room D.

The shrine platform in the middle of Room D also adopted the Baroque style, with extreme luxury and exaggeration, which was out of tune with the simple tunnel.

There was a gold-inlaid cup on the right side of the platform, and the left side was empty, with only a circular groove at the bottom.

Li Ang took the gold-inlaid cup and found that the bottom of the cup was connected to a metal chain, fixing the cup on the platform.

"They don't want me to take it away..."

He gestured with his palm at the cup's volume, which was indeed about three liters.

"The words on the platform say to put four liters of some kind of liquid, but this cup only holds three liters.

The empty space on the left side of the platform should be for me to find another cup,

And I also have to find some liquid..."

Li Ang looked down at the rubber suit he was wearing. There was no zipper on the suit.

"I don't have the urge to urinate now.

Even if I did, the normal daily urine output is about 1000-2000 milliliters, which is not enough to provide 4 liters unless I use fresh blood to make it up.

Considering the weakness of my body, it is also impossible to contribute two liters of my own blood.

I need to find another source."

Li Ang shook his head, left Room D, and came to the door of Room C.

On this door, there were some open-bottomed right angles and square patterns, and some right angles had a black dot at the top.

"What is this, abstract scripture?

Was the dungeon designer censored and could only use emojis to express his meaning?"

Li Ang squinted his eyes and observed carefully for a while, then suddenly remembered something and took out the letter written to Morgan again.

This letter had many water stains, smudges, and some small black dots left by scribbling.

He originally thought that this was because the writer's environment was harsh, his living conditions were poor, and he was also shaking his hand,

Which is why traces were left on the letter.

"The stationery itself has horizontal lines. The writer added extra vertical and diagonal lines in the middle of some English words, disguised as calligraphic errors.

But in fact, they are not mistakes, but hints.

Picking out each letter with vertical and diagonal lines, it should be

AdgBegCfijmpknQLorstvuwxzy..."

Li Ang raised his head again and looked at the door of Room C.

"There are hidden small black dots next to the letters jmpknQLorwxzy, which correspond exactly to the square and triangular patterns with black dots on the wall.

This is not an abstract emoji, but a pigpen cipher."

The so-called pigpen cipher,

Is a simple substitution cipher based on grids, that is, using a tic-tac-toe grid or a square grid to separate the twenty-four letters. ABCedfgi is a set of tic-tac-toe grids,

jkLmnopQr is a set of tic-tac-toe grids, with black dots in the corners to distinguish it from the previous set.

stvu and wxzy are each a set of diagonally placed square grids, and the latter is also marked with black dots.

When using it, you only need to cut out the corresponding letter patterns from the tic-tac-toe grid or square grid (such as a right-angled triangle with a black dot) to express the original ciphertext meaning.