The door control rumbled down behind him, Qiao Yun's eyes flickered slightly, this treasure house is not the same as the first three treasure houses, the treasure house is not a shelf but a glass display cabinet, some horizontal and some standing, filling the entire treasure house.

In the middle of the treasure house is a tall glass cabinet, in which a set of golden armor is quietly placed, and bursts of dazzling golden light reflect from the armor, which is eye-catching. His gaze only lingered on this armor for a moment, Qiao Yun walked towards a display case in front of him, this armor was just made of pure gold, although it was precious, but in Qiao Yun's opinion, it had no practical use, it was just a façade.

The old man was a little surprised that Qiao Yun didn't pay attention to the armor placed in the center of the exhibition hall, but he didn't say anything, but followed Qiao Yun silently around the arsenal.

Purple Cloud Sword, Thousand Transformation Sword...... A handful of sharp weapons were quietly placed on the red silk in the display case, Qiao Yun's gaze swept over the weapons, these weapons were indeed sharp, and each one was shining with a cold light, but it was not very attractive to Qiao Yun. First, Qiao Yun is not good at using weapons, and second, the appearance of these weapons is not Qiao Yun's heart.

Just as Qiao Yun glanced at the last showcase in the corner and was about to leave, his gaze suddenly froze, staring at an inconspicuous dagger at the very edge of the display case. The dagger was dark throughout, not emitting bursts of sharp and blue light like other weapons, but was so dull that if it weren't for its dagger-like shape, they would even think that it was nothing more than a piece of black scrap metal.

Taking a deep breath, Qiao Yun opened the display case and reached out to take out the dagger. Take it in your hand and look at it carefully. The old man saw that Qiao Yun didn't take other weapons, so he took out this inconspicuous dagger. The surprise in his heart was deeper, but the old man still said slowly: "I don't know how many years this dagger has been in the arsenal. I've seen it here since I first took over the agency. As for its origin, I don't know, but I know that it is called 'Dichen'. ”

Needless to say, Qiao Yun also saw the word "Dichen" written on the label where the dagger was placed. It's just that Qiao Yun is secretly smiling in his heart, this name is clearly a homonym, others may not know the material of this dagger, but Qiao Yun recognized it at a glance, this is a material called "tellurium iron" introduced in ancient books. This material is very rare, it is said to have been formed after the fall of the stars, its quality is extremely hard, the whole body is dark, and it is an excellent refining material.

His eyes flashed, and after seeing this dagger, Qiao Yun had already made up his mind, no matter what, he would take this dagger into his pocket, even if he didn't want black hay for the time being. Get this dagger too. Because it is too rare to encounter this kind of material, although Qiao Yun does not use the refining technique at all, but even so, this dagger is sharp enough. Moreover, Qiao Yun believed that if he mastered the refining technique in the future, he would definitely be able to train this material into a better quality dagger.

Qiao Yun's various behaviors made the old man very puzzled. Is there really anything wonderful about this dagger?" the old man shook his head, and quickly denied his idea. I don't know how long this dagger has been here. After a multi-generational change of the head of the Intelligence Agency, if there is really anything surprising about this dagger. It must have been placed in the most prominent place in the treasury, like the armor, rather than being casually discarded in the corner.

"I want this dagger!" Qiao Yun said as he looked at the old man.

Nodding, the old man said, "If you want this dagger, take it!"

"Thank you!" Qiao Yun was overjoyed in his heart, and immediately put the dagger into his arms, and with a movement of his divine sense, he put the dagger into the ring again. I didn't expect to come to this Li Hyogurt and actually be able to get "Telurium Iron", which is undoubtedly a great joy for Qiao Yun.

After accepting the "Telurium Iron", Qiao Yun casually walked around the Li Hyoku again, and after making sure that there was no more "Telurium Iron", Qiao Yun and the old man left the Li Hyogo and came to the last treasure house.

Wanfa Library is also slightly different from the first four libraries, not shelves and booths, but rows of huge bookshelves, if you don't know that this is Wanfa Library, Qiao Yun thought that he had entered the school library.

Rows of bookshelves are labeled in different categories, Qiao Yun stood in front of a row of bookshelves at random, took out a book from it and flipped through it, the three big characters of "Jin Wu Jue" came into Qiao Yun's eyes, and then Qiao Yun flipped through it, this book recorded the practice mantra of "Jin Wu Jue", as well as some essentials, common difficulties and solutions.

Putting the "Golden Martial Technique" back in its place, Qiao Yun's gaze swept over the books on this row of bookshelves one by one, "Heavenly Silkworm Golden Silk Technique" and "Ten Thousand Thousand Sword Techniques...... But seeing that all the mental formulas on the bookshelf were golden mental formulas, Qiao Yun was slightly aware in his heart, and walked to another bookshelf on the side again.

Sure enough, all the mental formulas on it are water attributes. With a sweep of his divine sense, Qiao Yun saw all the books in the treasure house, and these books were divided into five categories, namely metal, wood, water, fire, and earth. When he saw these five classifications, Qiao Yun's heart moved, he didn't expect the Intelligence Investigation Bureau to have such a complete range of mental formulas, and there were all five attributes of mental formulas, it seemed that he was able to find a suitable mental formula for Liang Hao, Zhou Kai, Qi Ze and others this time.

"These mental formulas should be of little use to you, after all, you already have a mental formula, and a martial artist can only practice one mental method formulas in his life, and you must know it! So this Ten Thousand Magic Treasury should be of no use to you, you better go to other treasure houses and take a good look!" The old man couldn't help but remind him when he saw that Qiao Yun was also turning half a round in the Ten Thousand Magic Treasury.

Qiao Yun naturally knew that each martial artist could only cultivate one kind of mental method, not only martial artists, but also cultivators, but what Qiao Yun had always puzzled was why he was able to cultivate both the "Easy Wind Control Technique" and the "Easy Control of the Mist Technique", but Qiao Yun couldn't find anyone to answer this question. Qiao Yun could only wait until he saw the master and then ask him about the old man.

"I'm not here to pick a mind method for myself, I want to pick a heart method for a few of my apprentices. Qiao Yun said.

"I see, then you can choose. The old man nodded, he didn't feel sorry for these mental formulas, although these formulas were accumulated by the Intelligence Investigation Bureau for hundreds of years, but there was no loss in letting Qiao Yun make a copy and take it away.

After hesitating for a moment, Qiao Yun looked at the old man and asked, "Chief Cen, I have a question!"

"You say. The old man was slightly stunned, he didn't know what questions Qiao Yun could have at the moment.

"How can I know what kind of mental formula a person is suitable for cultivating?" Qiao Yun asked a question that puzzled him for a long time, in fact, Qiao Yun kept saying that he wanted to find the mental formula for several people, and it was a reason that it was difficult to find the mental formula, and Qiao Yun didn't know what kind of mental formula a few people were suitable for cultivating.

The old man glanced at Qiao Yun and said with a smile: "Haha, it turns out that you are confused because of this! Okay, let me explain your confusion! The reason why this mental formula is divided into five kinds of gold, wood, water, fire, and earth corresponds to the five spiritual roots of metal, wood, water, fire, and earth. Not all people in this world have spiritual roots, there are actually not many people who have spiritual roots, and people with a single spiritual root are even more unique in a thousand, and these people are all cultivators who are very suitable for cultivation. As long as they cooperate with the appropriate mental method, their entry on the way to martial arts will be dozens of times faster than that of ordinary people. Two spirit roots and above are called miscellaneous spirit roots, miscellaneous spirit roots are a lot more than a single spirit root people, these people can also choose their own kind of spirit root corresponding to the heart method to cultivate, although this kind of cultivation speed is not as good as a single spirit root, but it is much faster than those who do not have a spirit root. Of course, the more spiritual roots, the worse the effect of cultivation, if it is a person with five spiritual roots of gold, wood, water, fire, and earth, it may not be as fast as a person who does not have a spiritual root, because the spiritual root is too mottled, which will seriously affect the progress of cultivation. ”

After listening to the old man's brief introduction, Qiao Yun had a preliminary understanding of the spiritual root, and Qiao Yun's heart brightened a lot, it turned out to be the case, that is to say, people without spiritual roots can also cultivate, but its speed is too slow, and it may not be able to enter the threshold of a martial artist in a lifetime. But those who have a single spiritual root can quickly upgrade and break through!

Qiao Yun suddenly thought that when the master found him, he said that he was a single spiritual root, but Qiao Yun suddenly wondered, what kind of spiritual root is this that he cultivates the "Easy Control of the Wind Technique", what kind of spiritual root is this?

Although he had doubts in his heart, Qiao Yun didn't ask the old man, not only did the old man not know his mental formula, but Qiao Yun didn't plan to expose too many of his things to others. Knowing that the mental formula corresponds to the spiritual root to be selected, Qiao Yun continued to ask, "Then I don't know how to see what spiritual root is in a person's body?"

"This can be measured with the Five Elements Bead. The old man said with a faint smile, and then took out a palm-sized white bead from his pocket. The beads are white and emit a faint halo, like a piece of jade.

Qiao Yun stared at the bead in the old man's hand and muttered, "Five Elements Bead?"

The old man nodded and said: "This Five Elements Bead is the only thing that measures the spiritual root in a person's body, and I don't know what the principle of this thing is, it is rumored that this is a measurement method left over from ancient times." There are not many of these Five Elements Beads left now, and only a little remains in the major hidden sects for testing and recruiting disciples. And the Intelligence Investigation Bureau is only a stock of this one. (To be continued......)