Xia Rufei, who had already retreated in his heart, suddenly felt refreshed.

The induction Yuye also responded, which means that he was not far from the boundary stone. He adjusted his internal breathing according to the "Big Dao Jue" technique, and his legs struggled to fetch water and continued to dive down.

Although the area under the strong light flashlight is still full of pool water and there is no bottom at all, Xia Rufei is very motivated.

The water in the pond became colder and colder, and Xia Rufei's teeth began to collide involuntarily, making giggling sounds.

If a practitioner can be so cold, the temperature of the pool of water can be imagined.

Under such circumstances, the consumption of true qi is also amazing. Even though Xia Rufei practiced the "Big Dao Jue" and the true qi is much thicker than that of the practitioners with the same level of cultivation, it cannot withstand such consumption. Gradually, he felt that he had not grasped a trace of strength.

Of course, he has reached this level and it is absolutely impossible for him to give up easily.

Xia Rufei has made up his mind and really can't support it anymore, so he can enter the spiritual map space. In that way, he can not only breathe, but also use the difference in time flow rate in the Yuanchu realm to meditate and restore true qi. I believe that in a short time, the spiritual map scroll will not be damaged in such an extremely cold environment, nor will it deviate too much from its original position.

However, Xia Rufei did not take out the spiritual picture scroll immediately, and he still wanted to challenge his limits.

I dived about fifty meters again, and the water pressure around me was already amazing. If I were an ordinary person who had not received professional training, my lungs would probably be seriously damaged.

Just as Xia Rufei gritted his teeth and was about to continue diving, the white raccoon in the space squeaked and gestured to Xia Rufei.

Xia Rufei has always kept in mind contact with Lingtu Space, and naturally he sensed the signal sent to him by the White Realm Li as soon as possible.

"Swim to the left?" Xia Ruofei said in his heart.

The white world ripped intently not to continue diving, but to swim to the left side of his body. Xia Rufei was slightly happy. Does this mean that he is approaching the boundary stone?

In any case, horizontal swimming is at least better than continuing to dive. Xia Rufei judged that if he continues to go down, he will dive at most fifty meters. Whether it is water pressure or the low temperature underwater environment, it should reach the limit that his body can withstand. Even if he hides in the space to recover his true energy, it will be difficult to dive further.

If he swims horizontally, he can still hold on for a long time by relying on his internal breathing. Even if he can't hold on, he can continue to persevere underwater as long as he changes breathing in the space.

I thought the boundary stone needed to dive to the bottom of the pond to find it, but Xia Rufei was also worried about this amazing depth of the pond. He didn't know when he would be able to see the bottom. Now he was secretly relieved.

Xia Rufei immediately turned his body and swam to the left. At the same time, the strong light flashlight in his hand shone forward, trying to see the situation ahead as clearly as possible.

The bottom of the pool was much larger than Xia Rufei imagined. He swam to the left for at least twenty or thirty meters, but still did not see the wall of the pool.

It is obvious that this is the shape of an inverted funnel, because from the shore, the range of the pool is not that large at all, but it is getting bigger and bigger as it goes down.

Xia Rufei could feel the induced jade leaves on his chest getting hotter, which made him feel much more at ease because it showed that he was getting closer and closer to the boundary stone.

The white rooster in the space became more and more excited.

Xia Rufei continued to swim forward for more than 20 meters, and finally, under the irradiation of strong light and flashlight, he saw the rugged rocky pond wall. Just about two meters in front of him, there was a black hole.

"Squeak! Squeak! Squeak!" The white zodiac jumped and screamed, and kept gestured with her forelimbs.

"Let me enter that stone cave?" Xia Ruofei asked with thoughts.

The white raccoon immediately nodded like a chicken pecking at rice. If the girl saw it, she would definitely be cute.

Xia Rufei did not hesitate, fetched water quickly with his legs, dived a little, and swam towards the hole.

Under the irradiation of the strong light flashlight, Xia Rufei gradually saw the appearance of the hole.

Its diameter is about one meter, and it looks like a very regular circle, with very smooth edges, which is completely different from the pool wall I just saw.

There is no doubt that this hole was dug by hand.

Who could have dug such a regular stone cave under the water nearly two hundred meters deep? Xia Ruofei couldn't help but secretly exclaimed.

He did not dare to neglect at all, and his mental power radiated out early, and the small amount of true energy was also swelling, ready to deal with unknown dangers at any time.

The entrance of the cave was dark, and it was impossible to see the situation inside, and it was difficult to extend the mental power. It was very similar to the situation he encountered in the strange white mist before he landed on this small island.

Xia Rufei instead put the strong flashlight in his mouth, held the military dagger tightly in his right hand, and stroked back with both hands. At the same time, his legs were swinging together, and his body lightly passed through the water, directly entering the narrow stone cave.

He felt as if he had passed through an invisible membrane wall. The cave was actually dry and there was not even a drop of water.

Xia Rufei still maintained a diving posture, and without any preparation for a while, he fell directly on the ground of the cave.

Xia Rufei opened his mouth in surprise. The strong flashlight fell to the ground, and the beam of light danced randomly in the cave. Only then did he wake up and quickly reach out and grab the flashlight.

The diameter of the cave is only more than one meter, so it is difficult to turn around here.

Xia Rufei grabbed the flashlight and shone it behind him, and at the same time he turned his head as hard as possible.

I saw that there was still a swaying pool water at the entrance of the cave, but the pool water seemed to be blocked by a transparent cover and would not flow into the cave at all.

Xia Rufei guessed that this should be the effect brought by the formation, but was still very amazed.

You should know that this is a water depth of nearly two hundred meters. The water pressure is amazing. It can block the pond water outside, but people can easily penetrate it. This formation is quite not simple.

Xia Rufei has been holding his breath since he got into the water. After entering the stone cave, he tried to exhale the turbid air and then took a light breath.

He suddenly found that the air in the cave was quite fresh, and it seemed that the concentration of spiritual energy was quite high. Although it was incomparable to the environment of the spiritual map space, compared with ordinary places in the outside world, this place can be regarded as a treasure land with rich spiritual energy.

Xia Rufei breathed a few breaths with confidence, and felt that his whole body was much more relaxed.

Although he can maintain his internal breathing state underwater by using the skills of "The Great Dao Jue", breathing is a human instinct. He still feels very stuffy in his subconscious without breathing for such a long time.

Now this feeling of depression has finally disappeared.

Xia Rufei did not stay at the entrance of the cave for too long. After a little rest, he began to move forward.

The diameter of this cave is only a little over one meter, and an adult can only pass through it, and he must crawl forward.

If you are claustrophobic, you may go crazy if you spend a long time in such an environment.

Xia Rufei has a strong psychological quality, and he still crawled forward calmly.

The cave has a downward slope, and the temperature inside the cave is also very low. Xia Rufei even feels that it is a little colder than in the pool water.

He held the dagger tightly in one hand, and his mental power did not dare to retract for a moment. In this cave, his mental power was greatly suppressed, and he could only detect three or four meters away in front of him.

As he continued to crawl forward, Xia Rufei felt that the cave gradually became spacious, and the feeling of cramping became lower and lower.

Of course, the temperature inside the hole is still extremely low, and the deeper the temperature, the lower the temperature.

It seemed that it had advanced more than a hundred meters. The width of the cave could accommodate an adult who bent down and walked.

Xia Rufei also sat up from the ground and leaned against the cave wall for a while.

After all, he had been crawling in the narrow corridor just now, and he needed to continue to use his true energy to fight the cold, so he was very tired along the way.

Xia Rufei took out a bottle of Lingtan water that modulated the petals of Lingxin Flower from the space, drank it down, and suddenly accelerated the recovery of mental power and true qi.

He sat for more than three minutes, then got up and hugged and continued to move forward.

The cave continued to widen and only advanced less than fifty meters. Xia Rufei found that the cave had a diameter of at least two or three meters. It was not only much spacious, but also had a height that allowed him to straighten his waist and walk normally.

This makes it much easier.

Xia Rufei moved forward carefully with the dagger in his hand, and his mental power was always exploring the surroundings, always keeping high vigilance.

The cave was very quiet, and Xia Ruofei could clearly hear the sound of his footsteps and the thumping heartbeat.

The induced jade leaves on the chest were so hot that it meant that the boundary stone was nearby.

The passage of the cave tilted slightly downward. Xia Rufei judged that the current position had already exceeded 200 meters from the ground.

Finally, after moving forward sixty or seventy meters, Xia Rufei saw a stone door.

This blue stone door should be made of a whole huge piece of bluestone, exuding an ancient atmosphere and is closely connected with the entire passage, and there is no switch or handle or the like.

Xia Rufei walked closer and soon found mysterious formation patterns engraved on the stone gate, forming a complete formation diagram.

After a little analysis, he had already calmed down a lot of this formation and the barrier formation beside the pool. Although the two formations are completely different, the idea of ​​setting up the formation is different.

Xia Rufei studied the barrier formation by the pool for a whole day and night, and had already understood the principles of the formation. Now it is much easier to analyze this formation.

He knew in his heart that this array map was the key to opening the stone gate.

Of course, it also takes a lot of time to analyze this formation.

Although it has been almost half an hour since entering the pool, the giant python is likely to have returned to the edge of the pool. Even if it cannot enter the inside of the formation, it is likely to stay outside the formation. But now that it has reached this point, Xia Rufei doesn't care about the giant python and open the stone gate with all his strength.

Anyway, even if you return the same way now, the giant python is very likely to have returned and may be caught even if you are caught.

The sensing jade leaves were already hot and the boundary stone was close at hand, so Xia Rufei naturally knew what to make a decision.

Now is not the time to consider the giant python at all. Only by calming down and analyzing the formation on the stone gate can you open it as soon as possible. The more anxious you are, the more counterproductive it will be.

Xia Rufei quickly remembered the entire array diagram firmly in his heart under the strong flashlight. Then he sat cross-legged in front of the stone gate, put the flashlight aside, and closed his eyes slightly and analyzed and practiced the formation in his mind.

Time passed by minute by minute, and the principle of this formation became clearer and clearer in Xia Rufei's mind.

Formation is also divided into schools.

Obviously, Xia Rufei's previous analysis and cracking of the barrier formation by the pool edge was very helpful to him in analyzing the formation in front of him.

A series of formation patterns form the basic array diagram, and a series of basic array diagrams form the formation.

Xia Rufei still starts with each basic array diagram, and then reverses the relationship between them.

Although I was doing the same job, the efficiency this time was much higher than the last time I analyzed the barrier formation.

He sat wither for about an hour, then suddenly opened his eyes and a relaxed smile appeared on his face.

"It should be like this!" Xia Ruofei said to himself.

He deduced it several times in his mind just now and basically confirmed the results of his analysis.

Xia Rufei stood up confidently and returned to the stone gate.
To be continued...