Feiya looked at the three roads in front of her.

The one in the middle is the main road. Looking from a distance, you can vaguely see the doors of some rooms.

The road on the right is the second widest, and some small doors can be vaguely seen, which seem to lead to some remote rooms.

The road on the left is the narrowest of the three roads and the most remote. It has only smooth walls and seems to lead to some indescribable depth.

She turned her head and looked at He Ao, "What's wrong with the road on the left? It seems the most dangerous?"

"Um?"

He Ao glanced at her and asked softly, "What is our fundamental purpose now?"

"Find the secret of this 'underground palace' and find the reason why the underground palace is close to the main world?"

Feiya replied thoughtfully.

"So where is this secret and reason most likely to be hidden?"

He Ao continued to ask.

"The deepest part of the underground palace?"

Feiya looked at He Ao, "Judging from the current situation, the supernatural power becomes stronger as you go down the underground palace. The powerful force that can pull the two worlds together is probably hidden in the deepest and lowest level of the underground palace."

"In fact, there is another place that shows that the secret of the underground palace may be hidden at the bottom,"

He Ao answered and took Feiya to the road on the left, "Based on what we have deduced so far, the underground palace was originally a large-scale facility used for some special purpose, and the designer of the underground palace at the beginning of the design

Considering the danger of the underground palace, blocking gates were designed on each floor.

"Based on this, if we use the first floor as a safe zone, the further away from the first floor, the more gates we will go through, and the greater the probability of being blocked. Therefore, if the original 'underground palace'

If there are any 'dangerous' items inside, they should be placed on the bottom floor farthest from the first floor."

He paused, "At this point, we have found a secondary purpose derived from the fundamental purpose, 'Looking for the lowest level or deepest part of the underground palace', because there may be something hidden there that can solve our fundamental problem.

"But the stairwell on the third underground floor is different from the stairwell on the second underground floor. There is no corridor leading to the next floor, only one corridor leading to the third underground floor.

"There are two possibilities in this situation. One is that the third floor is the last floor, so as long as there is one corridor, the other is that the underground palace has four underground floors, but the passages of the four underground floors are in another

The place."

"So," Feiya vaguely understood. She looked at the deep road in front of her, "This road may lead to the fourth floor of the underground palace? Why?"

"If we assume that the fourth floor exists, just imagine, why are the passages on the fourth floor not next to the passages on the third floor?"

He Ao asked casually as he walked along the road and stared at the scenery in the deep darkness.

"for safety?"

Feiya thought for a while and continued,

"If there is also a barrier at the entrance of the passage on the fourth floor, plus a barrier at the entrance of the passage on the third floor, then from the fourth floor to the second floor, you have to pass through two layers of barriers, which is worse than the two layers on the second floor.

The design of three layers of passages next to each other with only one barrier between them is more 'safe'."

"And this 'security' comes at the expense of convenience,"

He Ao used his flashlight to glance at the blood stains on the walls on both sides of the 'alley' where he was now.

"So the location of the passage on the fourth floor will not be too far from the passage on the third floor, so that the staff who go to the fourth floor to 'work' will not have to walk too much

"This road is closest to the corridor exit we just took, and there are no other rooms on both sides of the road. This will not allow the staff on the third floor and the staff on the fourth floor to squeeze into the same road and affect the traffic efficiency.

"From the perspective of moving line design, this is the road that should most lead to the fourth-floor passage among the three roads."

In fact, He Ao has another guess.

If the four underground floors of the underground palace really exist, the 'barrier' of the passage on the fourth floor may not be as simple as the corridors full of gates on the first three floors.

Otherwise, the designer only needs to design an extra-long gate channel and then open an opening in the middle to the third floor. There is no need to do anything extra and make the staff on the fourth floor take a detour.

"sharp!"

Feiya gave He Ao a thumbs up.

After figuring out the current situation, she turned her eyes to the deep road ahead. The two of them were moving very fast. At this moment, they were already a certain distance away from the road.

There was still a quiet darkness ahead, and there seemed to be a terrifying beast crawling in the endless darkness, opening its huge mouth, waiting to devour them.

She looked ahead with a flashlight and lowered her voice, "How long do we have to go..."

As soon as she opened her mouth, she saw He Ao making a silent gesture towards Qing Qing.

Then He Ao pointed to his ears and told her to listen carefully.

The two of them slowed down their steps at the same time.

Crunch—crunch—

When everything quieted down, some kind of thin, biting sound could be faintly heard from the depths of darkness ahead.

And while the two of them listened to the sound quietly for a moment, the sound suddenly quieted down and turned into silent silence.

The two looked at each other, slowed down their steps, and walked forward cautiously.

After walking a few dozen meters further, a pool of bright red blood with a gray gleam appeared in front of them.

In the center of this bloodstain, lay a mutilated humanoid monster. Its chest had been dug open, everything inside had been hollowed out, and its limbs also showed signs of being bitten by some sharp object.

Its head is somewhat human-like, covered with ferocious hair, and its eyes are widening at the moment, with the last trace of ferocity still showing in its eyes.

"He died not long ago."

Feiya lowered her head and glanced at the body, then spoke quickly in a low voice.

"Um."

He Ao nodded slightly. He glanced around and saw no obvious blood stains or footprints.

The two of them moved forward one after the other.

After walking a dozen steps forward, an open gate appeared on the left wall directly in front of the two of them.

They both had a meal at the same time.

He Ao looked at Feiya, pointed at himself, and then at the gate.

Feiya nodded quickly.

This is a division of labor, with He Ao looking inside and Feiya looking outside.

Soon, the two of them arrived at the gate, and He Ao shined a flashlight on the inside of the gate.

This is not a passage, but a large space of only about thirty square meters. Some simple blood-stained metal seats are densely placed in the space. At the innermost side of the space, there is a door with multiple doors.

A huge empty cabinet that was opened.

In the corner of the room, behind the small doors that opened, there was a small room with a toilet covered in blood.

While He Ao was looking at the scene in the room, Feiya was facing away from him, holding a flashlight to shine on the surrounding scenery.

She first looked around and found nothing. Then she thought about it and raised the flashlight.

At this moment, a huge, pale human face hung from the ceiling above her head and appeared in front of her eyes.

"ah!"

She screamed subconsciously.

A pair of sharp claws covered with spikes that looked like the hands of an orangutan suddenly stretched out and stabbed her neck.

Although she was startled, she did not panic. Instead, she suddenly took a step back, threw the flashlight forward, briefly blocked the two sharp claws, and at the same time reached out to her waist.

At this moment, a sword light suddenly shot out from behind her, stabbing the monster that fell on the ceiling, and instantly nailed it to the wall.

Only at this moment did Feiya see the appearance of this monster clearly.

It was a humanoid monster hanging upside down, with feet as wide and flat as fish webs, hands that looked like sharp claws, a slender head, pale cheeks, like the color of a person's face that had been dead for a long time, and jet-black fluff all over its body.

It was nailed to the wall, and blood with gray light left along the wound.

At this time, He Ao also walked out from behind Feiya. He glanced at the monster, quickly stepped forward and pulled out the bone sword.

Then he turned around and walked towards Feiya, "This should be the guy we heard the sound just now."

The flashlight that was just thrown by Fiya and fell to the ground after hitting the monster illuminated the scene behind He Ao:

The humanoid monster slid down along the wall, and when it was about to hit the ground, it suddenly opened its eyes, held its hands on the ground violently, and several tentacles stretched out from its feet, suddenly wrapping around He Ao's neck.

"careful!"

Feiya quickly stretched out her hand and shouted.

At this moment, He Ao, who was looking at Feiya with a smile and seemed unprepared, suddenly squatted down, swept his legs, and made a sword flower with the bone sword in his hand.

Lift it up.

Those tentacles passed through his head. Before the monster with the tentacles could react, it was directly knocked down by He Ao's sweeping kick and fell to the left.

But before its body fell completely, a white sword light slanting upward came towards it, directly cutting its body in half.

Immediately afterwards, He Ao used the potential energy of sweeping his legs to spin and jump, carrying his sword on his back, and stepped back several meters to avoid the splashing blood.
To be continued...