Before entering this cave, Fang Tiannan had tried to spread his perception to any open place in the valley. Specifically, Fang Tiannan was familiar with the terrain in the area near the valley, and the fluctuations of the yang attribute aura in any place.

In Fang Tiannan's mind, not only did he connect the fluctuation intensity of the Yang attribute aura with the terrain, but even in time, it was also connected, as if he had a clear map in his mind, marked with different points and curves. Every day at noon, where the yin and yang grass grows, the fluctuation of the yang attribute aura is the strongest. And with the passage of time, either in the morning or in the evening, the fluctuation of the yang attribute aura is the weakest.

Suddenly, after night fell, Fang Tiannan could still feel the fluctuation of such a "rich" yang attribute aura, which really surprised Fang Tiannan.

Subconsciously, Fang Tiannan began to investigate the fluctuations of the aura in the cave.

After about half a pillar of incense, Fang Tiannan frowned slightly.

"That doesn't seem reasonable. Fang Tiannan muttered to himself. As the perceptual exploration deepened, Fang Tiannan found that the fluctuations of the yang attribute aura in the cave were relatively average. After all, the entire cave is not very large. And the closer to the entrance of the cave, the fluctuation of the yang attribute aura became a little stronger.

In Fang Tiannan's opinion, it was as if all the yin and yang grass outside the cave, and the yang attribute energy emitted was concentrated in this cave. In this way, the fluctuation of the yang attribute aura that Fang Tiannan felt in the cave was even richer than what he felt when he stood in the place where the yin and yang grass grew luxuriantly at noon.

However, at night, will the Yin Yang Grass still exude Yang attribute aura?

In Fang Tiannan's mind, he couldn't help but start to carefully recall his previous experience outside the cave. Fang Tiannan didn't think about it, at night, he also stayed in the valley to rest, trying to perceive the yang attribute aura in this area. However, the fact is that once the sunlight disappears, the yang attribute aura emitted by the yin and yang grass will become much weaker. When the night begins to officially fall, the fluctuations of the yang attribute aura in the valley will also tend to be peaceful, and there is no difference compared to other places.

This made Fang Tiannan not very understandable, why did this cave at the moment appear in the fluctuation of yang attribute aura at night?......

couldn't figure out something, Fang Tiannan didn't take it seriously.

Since there was also a very good place to cultivate his perception at night, Fang Tiannan naturally wouldn't let it go. Just like in the daytime, Fang Tiannan began to spread out his perception and practice in the cave. Especially Fang Tiannan's posture, it was natural to meditate cross-legged.

This is the best way for a cultivator to perceive, and it is also the most suitable posture for cultivating perception.

When he was in the valley, in order to avoid people's eyes, Fang Tiannan spent most of his time standing, or bending over, or walking a few steps intermittently, to cultivate his perception. However, at this time in the cave, Fang Tiannan did not have so many scruples, and the spiritual power of the whole person was very concentrated. In addition, the fluctuation of the yang attribute aura in the cave was more intense than that of the outside world, and Fang Tiannan felt that the time he spent cultivating here for one night was comparable to cultivating outside for two or three days.

When it was getting dark, Fang Tiannan stood up and sighed: If you can cultivate like this every night, your perception should have a significant improvement, right?

However, even when the sky was bright, Fang Tiannan did not come out of the cave. Fang Tiannan really wanted to explore whether there were such strong yang attribute aura fluctuations in this cave during the day.

As a result, Fang Tiannan was naturally disappointed.

When the sunlight began to shine into this valley, Fang Tiannan felt that the yang attribute aura in the cave seemed to have long legs, and he ran out of the cave quickly, leaving not even a trace behind. Even if Fang Tiannan knew that there was a lot of Yin Yang Grass at the entrance of the cave, at such a close distance, Fang Tiannan still didn't perceive the aura of the Yang attribute.

"Even the valley outside, it's not as good?" Fang Tiannan glared and pursed the corners of his mouth, "There must be something weird!"

If Fang Tiannan hadn't had a chance to discover what was going on with the yang attribute aura in the cave when he entered the cave last night, then, at this moment, Fang Tiannan could almost conclude that the yang attribute aura in the cave was definitely related to the yin and yang grass growing in the valley.

As for the specific reason, Fang Tiannan is temporary, and it is unknown......

Throughout the day, Fang Tiannan stayed in the cave, eating the food prepared in the baggage, and resting for a while. Although it is said that meditation at night can also be regarded as rest, after all, Fang Tiannan's strength realm is only in the middle stage of the Transformation Strength Realm, and meditation can only restore the lack of strength in the body, but it cannot offset the physical exhaustion.

On the contrary, it was because of the cultivation of perception, Fang Tiannan's spirit was not bad.

And in the valley during the day, there were too many cultivators who had been trained, and it was inconvenient for Fang Tiannan to walk out of the cave rashly at this time.

When evening came, Fang Tiannan's whole body couldn't help but concentrate highly again. As time passed bit by bit, Fang Tiannan diffused his perceptual power, and he could clearly feel that the entrance of the cave seemed to have a fatal attraction to the yang attribute aura emitted by the yin and yang grass, and gradually gathered these aura outside the cave and poured it into the cave.

"Sure enough!" Fang Tiannan had long been suspicious of the existence of this cave.

Outside this place, there is a large area of yin and yang grass, and inside the cave, light source stones can be derived. There must be a strong correlation between the two. At this moment, the existence of the cave was also able to absorb the yang attribute aura emitted by the gathering of yin and yang grass at night, which made Fang Tiannan can't help but think that the light source stone he had obtained from the past would be formed in such an environment.

In the entire cave, every night, there is such a strong yang attribute aura, and it is very reasonable to want to generate light source stones over time.

Fang Tiannan was very curious, and carefully inspected the cave again. Whether it's on the wall or on the ground, nothing has been spared. It is a pity that Fang Tiannan did not find any traces left by manual excavation.

Perhaps, it is the time that has passed, which is too long.

Fang Tiannan thought so. After that, there is no longer any speculation as to why this cave coincidentally appeared here.

And with such an excellent place for cultivating perception as a cave, Fang Tiannan spent the next time cultivating in the cave at night, and during the day, he walked out of the cave and returned to the place where the yin and yang grass was lush in the valley to continue cultivating.

After nearly a month, Fang Tiannan could clearly perceive that whenever he diffused his perception, the surrounding scene gradually had a sense of solidity in his mind.

Considering that he and the sect had only applied for a month's training time, Fang Tiannan looked back at the location of the cave, and then at the large area of yin and yang grass in the valley, with a hint of a smile on the corner of his mouth, and walked out of the valley.