There must be a sound when the stone rubs against the stone, but at a depth of several hundred meters, the sound is negligible.

However, when the stone stick was pulled up, Yuebai and Lu Xiaohuang found at the same time that the water around them seemed to be flowing downwards rapidly, and even caused both of them to follow the direction of the water flow and fall downward.

The abrupt downward flow of the water would naturally startle the two, but fortunately, Yuelu and the others were mentally prepared, and the water did not take long to gush downward, so after a second or two, the two stopped diving and regained control of their bodies.

Immediately, Yue Bai and Lu Xiaohuang, who regained the initiative, swam back towards the hard ink stone stick above.

This time, Yuebai first asked Lu Xiaohuang to hold on to the rock to control himself, and then, the former pulled out the stone stick again, and after determining that he would definitely not be able to pull out the stone stick again, he pointed to the depths of the lake below, signaling to Lu Xiaohuang that the water flow just now was going down, and the entrance should be below.

"I'll take the lead, you pay attention to safety!"

As the god of water, Lu Xiaohuang naturally understood this superficial situation, she made a gesture to signal Yuebai to follow, and then, the two continued to go down again, diving towards the bottom of the lake that was still pitch black.

Soon, the two of them dived more than ten meters deeper, and finally saw a big hole in the rock wall of the lake in the east.

The hole is still a doorway, with no decoration or door panels, only a complete darkness with no light.

However, the Moon Sect Master, who possessed the Divine Eye of Argument, found that there seemed to be a very disordered aura gathering phenomenon inside this doorway, especially in the dark area inside.

That is to say, after Yue Bai looked along the doorway, within his line of sight, several streams of heaven and earth qi with different colors, flow speeds, and attributes appeared.

Of course, among these intertwined heaven and earth qi, the most huge and rich nature is still the water vitality, after all, the inside of the door hole is also a water rock cave filled with water from the heavenly pool.

"The breath is starting to get complicated, be careful if you continue!"

Yue Bai wrote such a sentence from the underwater drawing board and handed it to Lu Xiaohuang to show his discovery.

But the water god didn't care, Lu Xiaohuang waved his hand indifferently, made a gesture to continue, and then probed, his body was lying on his stomach, and he swam in.

Yuebai saw that the other party didn't care, so she smiled bitterly and followed the other party into the doorway.

But the Moon Sect Master was more careful, and when he passed through the doorway, he also deliberately looked at the doorway, as if he wanted to see if there were any mechanisms around the doorway, and whether it had anything to do with the stone stick just now.

And looking at it this way, Yuebai did find that there was a long groove in the shape of a long strip at the top of the doorway, and at the same time, there was a stone pin in this groove, and at the bottom of this doorway, that is, at the lower mouth of the doorway corresponding to the stone pin above, there was a stone door groove with a stone slab shrunk down!

The status quo is already obvious, this is clearly the hard ink stone stick just now is a mechanism device, as long as someone pulls the stone stick there hard, the stone stick just now will pull the mechanism, trigger the stone pin here, and then let the stone pin lift up, open the slot that is stuck in the stone door, let the stone door retract below, and open this black doorway.

But where is the inside of this doorway? If there is no danger here, then why should the hard ink stone stick used to open the door be placed so high?

Could it be that the role of the stone stick is not only to open the door, it also has other functions, so it has to be placed on the top of the underwater stone cave, more than ten meters high?

But at this time, Yuebai was no longer allowed to think about the answer, because the moment he was stunned, Lu Xiaohuang, who was leading the way in front, had already gone deep into the darkness, if it weren't for the underwater miner's lamp on the other party's head, then Yuebai really couldn't find the other party.

There was nothing in front of him, and there was no other light in the cave except for the two miner's lamps in front of and behind him.

Moreover, from the beginning of the doorway, the two of them passed up and down, left and right, and it was still very rough, but when they did not stop going deeper, the four rock walls on the upper and lower sides of Yuelu and the two began to show signs of artificially repaired smoothing.

That's right, this must be a tomb passage, and at the same time, the size of the current space also indicates that this is an escape tomb for craftsmen after the ancient tomb is closed.

However, on the left and right sides of this tomb road, there are no things that Yuebai recognizes.

So to speak... What should exist here?

Let's take for example the murals related to ancient tombs.

The murals are used to record the real events that happened before and after the construction of the ancient tomb, and in the current era, and in the general escape route, whether it is before or when the craftsman escapes, there will also be some murals left to show the important events that the tomb owner has really done.

But there are no frescoes here, and other than that, there are no oil lamps on the tomb walls for lighting, or wall patterns for decoration, which should be supposed to be, but none of them appear.

Also, when he continued to swim with Lu Xiaohuang, Yuebai seemed to notice that in the places he had passed, the rock walls on both sides of his side, including the top of the tomb road, did not look like the usual moon soaking in water.

In other words, Yuebai found that on the four walls of this tomb, there were some fine bubbles similar to those on the surface of a dry object that had just been soaked in water.

"Isn't it strange that this graveyard wasn't filled with water before?"

Yue Bai seemed to be very interested in this detail, he saw that the tomb cave in front of him seemed to be straight, so he was not afraid of not being able to catch up with Lu Xiaohuang, so the Moon Sect Master subconsciously slowed down his swimming speed, and looked at the rock walls on both sides of his body for a detailed look.

And this look, Yuebai also confirmed his guess.

Sure enough, the upper half of the entire tomb road, that is, the half section of the rock wall on both sides of the tomb road, really has obvious signs of dry and wet.

And this result can also prove that before the trigger mechanism is opened, once the stone door at the end of the tomb and on the other side of the door is closed, the inside of the tomb will not be filled with the water of the heavenly pool, at most, it seems that it can only be filled halfway, and it will not be able to flood the entire tomb.

However, if the current tomb was closed and half flooded, does this prove that no one used the tomb itself when it was built and closed after the tomb was completed?

(To be continued.) ）