The river is very slow, the water is not deep, just up to the waist. The bottom of the river is dense and full of pebbles, and there are no grains of sand, so it is very comfortable to step on.

As we got farther and deeper, the light began to dim, and after a kilometer it was completely dark. Cheng Yifan used spiritual power to avoid seeing objects within 100 meters.

The river was not long, and after walking for an hour, Cheng Yifan was blocked by a huge rock wall. Because the water flow is not fast, Cheng Yifan does not walk slowly. According to the time, this wall is less than 3,000 meters away from the grotto.

There is an inverted triangle opening at the bottom of the rock wall, and the widest part is about half a meter, just enough to pass half a body. Cheng Yifan guessed that he was washed into this river from that opening.

The triangle mouth is below the surface of the water, which means that from now on, Cheng Yifan can only dive forward.

Cheng Yifan's spiritual power is now more than ten times stronger than when he fell into the swamp. He could hold his breath in the water for more than half an hour in his previous heyday, and he conservatively estimated that he should not have a problem staying in the water for five or six hours. So he didn't stop, and quickly got into the opening.

Probably because of the narrowing of the waterway, the water flow in the mouth is much faster than the river outside, and the resistance to Cheng Yifan's progress is also a lot greater, plus he is crawling forward, so Cheng Yifan's forward speed is much slower.

He still overestimated himself, or rather, he underestimated the environment here, and he felt that with this kind of high physical exertion, he could only hold his breath for three hours at most.

Fortunately, this opening is not very long, and after Cheng Yifan dived and climbed for half an hour, the opening became wider and wider, and his speed also increased.

After another half an hour of climbing, he finally came out of this opening, only he was still in the water and still needed to hold his breath. Aside from being able to stand upright, the situation has not improved much.

At this time, in front of his eyes were endless dark waters. He could only see a hundred meters, so he couldn't be sure how big this water was, but in his consciousness he felt that this water was so big that he couldn't imagine it.

He looked up and swam to the surface of the water, because he had been holding his breath for more than an hour, and he had to go to the surface of the water to change his breath and take a look at the situation on the water. However, when he swam more than ten meters down, he was disappointed. Within his visual distance, he saw that the path to the water was blocked by the endless rock face.

There was an infinite stone wall cover above his head, and the lid was covered with countless holes, which looked like a beehive, densely packed with round openings of comparable size, not wide, about half a meter.

He swam for more than half an hour, but still under the huge lid, the top of his head was always densely packed with round openings. He found a random opening and swam towards it for another half an hour, but he still couldn't get out of the water, so he had to go back the way he came.

Until now, he has been sneaking in the water for more than three hours. His spiritual power had been almost exhausted, and the golden spiritual root began to slowly dim. With the experience of depleting the spiritual root twice, where did Cheng Yifan dare to mess around, he did not hesitate to turn around and make a triangular opening.

"Whew, whew...... Whew, whew......! Cheng Yifan drilled into the mouth, climbed onto the riverbank, and gasped for breath.

He was very happy, he had made a correct decision just now, and resolutely turned back, otherwise this time his spiritual root would be finished, and he stayed in that water for five hours, which was seriously beyond his bearing.

After a while, he began to recuperate cross-legged, and at the same time took out the spirit yuan to replenish the spiritual energy. The time of recuperation passed quickly, and when Cheng Yifan recovered his state, it was already the night of the same day. In the meantime, he used his spiritual power to find a way out, but the countless beehive holes were as numerous as the stars in the sky, and he couldn't start at all. In desperation, he could only go back to the cave and continue to rest.

He already had a plan in his heart, and in the next few days, in addition to finding an exit, he would have to step up his spiritual training. Although the effect of cultivating spiritual energy in the spirit absorption technique is far less easy than absorbing the spirit element, it is more than a hundred times faster than the ordinary spirit absorption technique. Moreover, when Cheng Yifan was practicing the spirit absorption technique, he unexpectedly found that the aura here was very pure. He was confident that if he could live here for a year and a half, he would be able to break through to the second floor. However, he didn't want to stay here for a year, no one likes to be alone, and no one wants to be buried under a lake for a year.

On the third day of falling into the cave, that is, the seventh day of Cheng Yifan's entry into the mountain, a creepy howl came from Wuyun Mountain, like the bitter howl of evil ghosts, and the howl resounded throughout Wuyun Mountain. This voice can be heard in the other world, outside the other world, in the Wuyun Mountain, and outside the Wuyun Mountain.

Cheng Yifan can naturally hear this howl, and the sound comes from nowhere, but it can be heard clearly, as if it sounded in his ears. That voice made Cheng Yifan very uneasy, not afraid, but worried, because he could hear the familiar breath from that voice.

"Seven days howl!" Cheng Yifan remembered the seven-day howl that Gao Yunliang talked about when he was in college. Calculating the time, it happened to be the seventh day of their entry into the mountain.

It's just that Cheng Yifan didn't know: "At this time, in the different realm, a funeral ceremony is being held in the Sealing Spirit Realm in Wuyun City. ”

And Gao Yunliang, Ye Feifei and the others who participated in the funeral, did not know: "Wuyun Mountain, which is outside the other world, has also fallen into chaos at this time. ”

The reason for the chaos outside the other world is not only because the howl can make all creatures palpitate, but more importantly, the seven days of howl have cut off the hope of many people.

Three hundred years later, Wuyun Mountain finally gathered five people with the surname to enter the mountain, but the people of the five great families still heard the "Seven Days Howl." ”

The people of Wuyun Mountain outside the other realm don't know what is going on with these seven days of howling? All they know is that this sound appears once every 25 years, after the seventh day of the mountain's entry.

And once this voice appears, it means: "Those who go into the mountains will never come back!" They hated and feared the sound as much as they could, but they knew where it came from and what the "howl of the seven days" was all about!

That is, on the day he heard the "Seven Days Howl", Cheng Yifan felt the breath of an unknown creature coming from the other side of the waterfall.

"Yes, it's the breath, not the smell." This aura is the terrifying aura he sensed when he fell into the swamp that day.

The terrifying creature seemed to be terrified of the howl, and Cheng Yifan could feel it trembling, and it seemed to have come back for refuge. Fortunately, it was so frightened by the howl that it could not notice it when Cheng Yifan touched it.

Driven by curiosity, Cheng Yifan actually opened the Sky Eye Vision, wanting to see what that terrifying creature was? It's just that the cave on the opposite side is darker, and he can't see it clearly. All I knew was that it was a very large creature, with legs and wings.

When Cheng Yifan increased his spiritual power output and wanted to explore the realm, he accidentally touched the barrier circle of the terrifying creature.

Cheng Yifan could see the creature's giant eyes that suddenly opened, and he immediately cut off his spiritual power, and said uneasily in his heart: "I don't know if it has found me?" ”

He hurriedly got up and fled into the depths of the cave, while shielding himself from all fluctuations in spiritual power.

"Hopefully it didn't find me." Cheng Yifan was at the end of the river, hiding for two days, he only knew that the howl had stopped for a long time, but he didn't dare to move his body, for fear of being discovered by the terrifying creature.

It was very dark there, and Cheng Yifan didn't dare to practice, nor did he dare to use spiritual power. I don't know how long it is, although it is only two days, he feels that several days have passed.

Finally, he couldn't help it and sneaked back into the cave. Fortunately, the creature had left, and Cheng Yifan escaped again.

He cautiously stepped out of the platform, only to find several huge footprints on the platform, like the soles of giants. He knew that the horrible creature must have been here, probably because the river inside the cave was too narrow to get in.

Cheng Yifan didn't know if the creature had already discovered himself? But he didn't bother with it, because he knew that he was safe at the moment, and even if the thing came back suddenly, he could hide back in the river of the cave, and he was very sure that the creature would not be able to enter the depths of the cave.

Now the most urgent thing for him to do is to absorb the spirit, because only when the spiritual power becomes stronger, can he have a way to leave. Whether it was to leave through the mouth of the water hive in the cave, or to jump over this waterfall and go to the cave on the opposite side, he needed to have enough spiritual power.

Thinking of this, he immediately crossed his knees and began to practice.

This practice is more than half a month.