Last night, Lin Yu tried to activate the four-elephant array around the villa for the first time, and successfully stopped Tang Jiu outside, indicating that the effect of the formation was very successful.

But at the same time, it also exposed a problem, Lin Yu did not have the spirit crystals that could provide spiritual power to the Four Elephant Array at hand, resulting in this Four Elephant Array could only be activated by Lin Yu's own spiritual power, which became meaningless.

That's why Lin Yu would spend a whole day going out, collecting hundreds of stones with different textures from a radius of dozens of miles, trying to artificially make spirit crystals.

Spirit crystals are very common items in the cultivation realm, generally in places where the spiritual energy is strong, and the spiritual energy will attach to the underground ore veins for various reasons, forming crystals.

These crystals are the prototypes of spirit crystals, and the crystals are tempered by high temperature and huge pressure underground, and after a long time, they finally condense into high-density crystals, which are spirit crystals.

Spirit crystal is a solid spiritual power, which can provide spiritual power support for formations or magic weapons, and because it is very versatile, it is regarded as a common currency in the cultivation realm.

Spirit crystals are divided into multiple grades according to different qualities, and there are some rare spirit crystals with special attributes, which are even more valuable.

Lin Yu didn't even have the lowest-level spirit crystal on hand now, which seriously affected his next cultivation plan, so he had to find a way to artificially create a useful spirit crystal in this world without spiritual energy.

To be precise, it is to make a usable spirit crystal prototype, the real spirit crystal has to go through hundreds of years of underground burial to form, Lin Yu does not have that much patience.

The prototype of the spirit crystal is not as stable as the spirit crystal, and it will volatilize and diffuse when exposed to air, and it will only have a shelf life of a few months, but for the current Lin Yu, it is enough.

The key is that the adsorption capacity of various rocks to aura is different, and there must be enough adsorption capacity to be used as a deposit for the formation of spirit crystals.

Lin Yu really hadn't studied this aspect, after all, only the worst disciples in the sect would be sent to the mine to dig spirit crystals, and this kind of physical work had never been related to a genius like Lin Yu.

Therefore, Lin Yu had to find as many samples as possible, and then find the most suitable mineral deposits from them.

After the deposit is determined, the source of spiritual light can be placed in it, and then a small Luo Tian array can be made with the broken longan jade, so that the source of spiritual light can release a high concentration of spiritual energy in a small area, which will be adsorbed on the deposit to form crystals.

The plan was like this, Lin Yu took out the source of spiritual light and put it on the table, the crystal gem emitted a brilliant light, constantly exuding a trace of spiritual energy outward.

Lin Yu picked up the stones on the table, stacked them one by one around the source of spiritual light, and finally piled a small mountain on the table, burying the source of spiritual light deep in it.

Overnight, come tomorrow morning to see the results.

At that time, according to whether there are traces of aura crystallization on the surface of these stones, you can distinguish the difference in the aura adsorption capacity of various rock materials, and choose the most suitable one.

......

Early the next morning, Lin Yu returned to the underground dojo to check the results, but the reality made him very disappointed.

Of the more than 100 kinds of stones that were used for testing, none of them could condense spiritual energy crystals, and Lin Yu checked every stone, but he didn't find even a trace of spiritual power crystals.

Lin Yu was disappointed, he expected that these stones he was looking for temporarily might not be suitable for making ore deposits, but there was no trace of spiritual power crystallization, and the result was really too bad.

Is there really no way to artificially create spirit crystals?

Lin Yu left the dojo sullenly and returned to the restaurant on the first floor to have breakfast with his daughter.

Xiaomeng saw that her father was in a bad mood, and tried to find a way to find words: "Dad, we are about to reach the end of the term, Teacher Zhang said that this is our first final exam, everyone should take it seriously!"

Lin Yu nodded: "You usually completed your homework very well, and the most important thing is to keep a normal mind in the final exam." ”

Lin Xiaomeng pursed her lips: "No~ It's usually usual, and the final exam is the final semester~"

Lin Yu smiled: "Strength is based on the accumulation of every moment of every day, and your daily study and homework in the past half a year have determined your final grades, so don't be nervous." ”

"Oh well. ”

Lin Xiaomeng saw her father smiling, and she was also happy: "Grandpa Huang, the sugar on this bread today is so sweet~"

Uncle Huang laughed: "This method is called frosting candy, if you like to eat it, I will make more tomorrow." ”

Lin Yu picked up the bread in front of him, the surface of the full bread was wrapped with a layer of white cotton candy, and the silk was like velvet.

Lin Yu's heart moved slightly: "Uncle Huang, how is this frosted candy method?"

Uncle Huang was stunned, he didn't expect Lin Yu to be interested in this.

"Just heat the cotton candy slightly, sprinkle it on the freshly baked bread, and then put it in the refrigerator and freeze it for a few minutes. ”

Lin Yu's eyes lit up: "Cool down! Why didn't I think of it before!"

After breakfast, Lin Yu put the bread back on the plate and stood up.

"Uncle Huang, I'm going to move the refrigerator to the basement to use it. ”

Uncle Huang was a little confused, and he didn't know what he was going to do with the refrigerator.

Mr. Lin...... There are still a lot of ingredients in the refrigerator, and if you take it out directly without low temperature storage, it will be bad. ”

Lin Yu frowned: "Then you accompany me to the city today and buy another refrigerator for the family." ”

Lin Xiaomeng, who was eating bread, suddenly rushed to speak: "Dad, Dad, don't we still have a refrigerator at home in Jiayuan Community, just move that one to use, you can't waste money~"

Uncle Huang couldn't help laughing: "Xiaomeng is really sensible, she understands diligence and thrift at such a young age." ”

Lin Xiaomeng snorted proudly, and her pigtails went to the sky.

Lin Yu thought about it and nodded in agreement: "Okay, let's go back to Jiayuan Community after sending Xiaomeng to school today, and move the refrigerator over there here." ”

After breakfast, Uncle Huang drove Lin Yu and Xiaomeng down the mountain, and after dropping Xiaomeng to school, he drove to Jiayuan Community.

Previously, because of the source of spiritual light and the rampage of the dragon's eye jade, there had been a huge riot in the building where Lin Yu was located, but as time passed, it was calm again.

Let Uncle Huang contact the transport vehicle at the gate of the community, Lin Yu took the elevator to the sixth floor alone, came to the door of his house and pushed the door to walk in, the house was deserted, and it was exactly the same as before leaving.

Lin Yu walked directly towards the kitchen, and suddenly kicked something under his feet, making a soft sound.

He looked down and saw a red envelope on the ground, which seemed to have been stuffed under the crack in the door.

Leaned over and picked up the letter, and there were two bright big characters on the cover: War Book.

Lin Yu frowned, opened the envelope and took out the letter inside to unfold it, the content of the letter was very simple.

In the last battle of the martial arts, it was unconvincing for you to win the battle opportunistically, so if you have the guts, please fight again.

Tomorrow, Gu Wansan is waiting in Trinity Hall!

The time to settle the payment is yesterday, so the time for the other party to challenge is today.

Closing the letter, Lin Yu frowned: "Gu Wansan, who is here......