However, after practicing the Spiritual Movement Period Exercises to the fourth layer, Lin Xuan also encountered a problem, that is, the effectiveness of the Purifying Pill was greatly reduced, making his cultivation difficult again and slowing down.

The road of cultivating immortals is getting more and more difficult in the back, obviously, with the improvement of Lin Xuan's skills, the lower grade marrow washing pill has gradually been unable to meet the demand.

Originally, according to common sense, the quality of the pill is poor, and it can be made up for in terms of quantity by taking more, but the problem is that the "Commentary on the Pill" makes it very clear that the number of pills taken per day should not exceed nine pills.

That's a bit of a dilemma.

After some careful consideration, Lin Xuan had to make the next decision and try to purify the medium-grade marrow cleansing pill again.

Because according to the annotation of the pill, the upper limit of the pill pill is nine pills per day, but there is no specification of which grade of pill it is, in other words, the lower grade pill can be taken up to nine pills a day, and the more effective middle grade pill can also take nine pills a day.

Since the low-grade pill can no longer meet the demand, then of course there is only the idea of hitting the middle grade, although when he had just researched the magic of the Blue Star Sea, Lin Xuan had tried to use it to purify the mid-grade pill, but the result was very hard, and he failed at the very end.

But now the situation is different, at that time, he was only the cultivation of the second layer of the spirit period, and now it is the apex of the fourth layer, and the blue sea of stars is growing simultaneously with the spiritual power, after the improvement of the power, the volume of the sea of stars has also increased a lot, of course, Lin Xuan does not dare to say that he can succeed one hundred percent, but in the case of the deterioration of the effect of the lower grade pill, purifying the middle grade is already the only choice.

After making a decision, Lin Xuan began to try, he rested for a while, and waited for the spirit, mana, and the sea of stars in the dantian to all recover to their best state.

Then Lin Xuan sat down cross-legged, poured out a low-grade marrow cleansing pill from the jade bottle, held it in his hand, and released his divine sense, now Lin Xuan's cultivation has reached the fourth layer of the spirit period, not only the spiritual power has risen sharply, but the divine sense has also been greatly enhanced than before, when it is released with all its strength, it can cover a radius of ten meters, and it is delicate, even if it is the sound of ants crawling, or the sound of a needle falling to the ground, it can't escape his grasp, it is a very wonderful feeling.

Of course, this is nothing, it is said that the divine consciousness of high-level cultivators can even scan a radius of a hundred miles, and the cultivators of the Yuan Infant Stage can even travel to the void, of course, those are just legends, with Lin Xuan's current strength, it is impossible to have the opportunity to meet those masters.

The top priority is to purify Zhongpindan.

Thinking of this, Lin Xu began to mobilize the blue light points in his body, countless blue lights gathered together, converging into a beautiful blue ribbon, moving along the meridians, this process was very difficult before, it can be said that it was extremely difficult, but now it is much easier, how to say that Lin Xuan has purified thousands of waste pills, practice makes perfect, and with the improvement of his skills, the meridians are also stronger than before, and the endurance is stronger, so this process no longer has the jerky feeling before.

Soon, the point of light moved along the meridians to the wrist of his right hand, and Lin Xuan concentrated his divine sense, all of which were applied to the pill.

Suddenly, a wonderful situation happened, the Myelin Cleansing Pill was magnified several times in his mind, and Lin Xuan's divine sense easily entered the inside of the pill, and he could see the essence and impurities clearly.

Carefully control the flow rate of the light spots, let them slowly enter the pill in order, and then the purification begins, inside the snow-white pill, there are some black things, these are the impurities that affect the efficacy of the medicine, the so-called purification, is to get them out.

This process is very difficult, because these impurities are very tightly entangled with the essence, but the blue light spot can do it, when it flows and encounters the white essence, it passes directly through without barriers, and when it encounters black impurities, it pushes them outward a certain distance.

However, unlike when the waste pill was purified into the next product, the impurities at that time were powdery, that is, solid, so it was easier to push the light spot, but now these impurities are thick, semi-liquid things, and it is very difficult for the light spot to separate them from the essence.

Impurities of the same size used to be pushed by only one point of light, but now there are at least three points of light, or even five, the last purification failure was because the energy of the blue sea of stars in Lin Xuan's body was not enough, so now, can the volume of the sea of stars support until the end of purification.

It is important to know that the purification process of the Dao cannot be interrupted, that is to say, it cannot be purified half of it today, and it will be repeated tomorrow, either it will be a success, or it will be completely scrapped, you must know that in this case, Lin Xuan has no way to purify the scrapped pill again, and it has really become garbage.

However, before trying, Lin Xuan had also thought about it, with the current energy of the Star Sea, the chance of success was still more than seventy percent, but that meant that there were no accidents.

Up to now, Lin Xuan's Pindan has been purified a lot, but Zhongpindan has only tried for the second time, and the first time ended in failure, so whether there will be a sudden situation, Lin Xuan is not sure.

But even if it appears, there is nothing, anyway, there are enough of my own lower grade marrow washing pills, even if the purification fails, it is not a pity, continue to sum up the experience and then try the test, slowly it will always succeed, just like purifying the waste pill into the next grade pill, at the beginning it is not very jerky, and the success rate is low, and now I feel relaxed and comfortable, which is a familiar process.

With such psychological preparation, Lin Xuan was not afraid of failure, and he was assured to purify boldly.

At the beginning, it was smooth sailing, although it would take more light point energy to push the semi-liquid impurities, but with the current volume of the Star Sea, it should be enough.

However, when the impurities are gradually separated from the essence part and pushed to the edge of the elixir by the light spots, they do not move at all, that is, they cannot be discharged.

How so?

When he was pure under the premise of Pindan, he had never encountered this situation, Lin Xuan frowned, but he was not panicked, and he couldn't solve the problem in a hurry, so he had to analyze the situation calmly.

He gathered his consciousness and looked at the edge of the pill, only to see that unlike the inside of the pill, the edge of the pill seemed to be semi-liquid.

"I see. Lin Xuan maintained the flow of blue light, and began to analyze, when purifying the waste pill into the lower pindan, the impurities were also powdery solid, so it was easier to wear out of the pill, and when purified into the middle pindan, the impurities were semi-liquid and viscous, so it was not easy to get out.

That's how it should be!