The spring breeze blows, dispelling the remaining cold of winter. In winter, trees that lose their leaves begin to sprout green buds on their branches.

Compared to winter, the clothes of the students in the classroom are much thinner.

"You're almost in sixth grade, and most of the theory has already been taught. As graduation approaches, you need more time to practice and master the skills of ninja. Therefore, in the future, you will have more practical classes and fewer theoretical classes. Walking into the classroom, Sugimoto announced that the curriculum would be adjusted in the future.

"Today, I want to talk about the last important content in the theory class, and after the lecture, there are only some small things left in the theory class."

The students in the audience heard that there would be fewer theory classes, and their emotions were relatively high.

"The theoretical knowledge of the Transformation Technique and the Doppelganger Technique in the Three-Body Technique has been taught to you, and what you need after that is to keep practicing until you are able to use them proficiently and learn to use them flexibly. Today, I'm going to start teaching you the last of the three body techniques, the stand-in technique. ”

Writing the words "Stand-in Technique" on the blackboard, Sugimoto turned around and said, "Among the three-body techniques, the stand-in technique is the most difficult and the most useful. From weak to lower forbearance, strong to supreme forbearance, there will definitely be times when it is necessary to use the stand-in technique. ”

"The stand-in technique allows you to make the stand-in item your own and induce the enemy. And when the enemy thinks they have succeeded in attacking you, you can take the opportunity to fight back. In a sense, the Avatar Technique can be regarded as a variant of the Transfiguration Technique, except that the Transfiguration Technique changes oneself into another form, while the Avatar Technique changes other items into one's own appearance. In the same way, the stand-in technique is somewhat similar to the doppelganger technique, both of which allow things that are not to act on their own......"

Hearing this, Aoyagi was a little distracted. The similarity between the doppelganger technique and the stand-in technique that Sugimoto mentioned suddenly made his mind burst into inspiration.

The doppelganger technique and the stand-in technique can all make items or phantoms other than themselves act autonomously, doesn't they have self-awareness? It's the same as shadow clone.

Since these three techniques all have the same parts, by analyzing the chakra changes and operations of these three techniques and finding out the same parts, wouldn't it be possible to find the chakra changes and operation methods that realize the consciousness-giving function? Later, it will be possible to add this consciousness-granting structure to ninjutsu, allowing it to track enemies on its own.

(For the sake of expression and research convenience, the definition is made here, and the sum of the chakra changes and operation modes that can achieve a complete function is a chakra functional structure, referred to as the structure.) Ninjutsu is generally composed of multiple chakra functional structures. ）

And the rest, the part of the structure that is unique and different from each other in the three ninjutsu, the clone technique should mainly be the structure of creating illusions, and the shadow clone technique should be a structure that shapes the physical body, divides the chakra equally, and recovers the chakra.

Aoyagi was delighted to be unexpectedly inspired. And what excites him the most is not that he has the possibility of adding will to ninjutsu and realizing "the law has a primordial spirit", but that he has the idea of continuing to study ninjutsu in depth, and proposes a theoretically feasible method of analyzing ninjutsu.

Aoyagi was very confused before, and didn't know how to start figuring out the specific way in which ninjutsu realized the function of will. He tried to start with the mudra, but there was a problem, the mudra was not the decisive factor, even if he made the same mudra, driven by the spirit containing different wills, the chakra in his body would change differently. It's not feasible to start with the mudras and figure out how the various functions are implemented.

And after being inspired by Twilight last time, Aoyagi also thought about directly studying how chakras change and how they worked. However, it is too much to find a needle in a haystack by directly analyzing the functional structure of chakra in the body and slowly deducing how various functions are realized.

So how many parts should the complex chakra change process be divided into? Where should each part start and where should it end? This is a problem that cannot be avoided in this way of research.

If you divide the scope one by one, list the various possible combinations (there must be a lot of them), and then study them one by one, it takes too much time, and it is completely a matter of luck. In addition, this requires a high level of chakra control, and you have to be able to implement various chakra changes and operation methods in your body individually, and test their effects one by one. Overall, this approach is not very feasible.

Nowadays, comparing the functional structure of chakra with similar functions in ninjutsu, it is easy to find the same structure. And the function of this structure is likely to be the one they share. This is much faster and more feasible than slowly groping.

Although he hasn't actually done it yet, Aoyagi thinks that this method should be feasible and plans to put it into practice as soon as he returns.

As long as this experiment is successful, it means that there will be a more efficient way to study ninjutsu in the future. Compared to starting with mudras before, this method is closer to the essence of ninjutsu.

Aoyagi retracted his fluttering thoughts and continued to listen carefully. After all, the rest of the research will have to be carried out when I get back home. The stand-in course that is being conducted now is still quite important.

This paragraph is a long story, but it only happens in the mind, and it doesn't take much time, and Sugi is still introducing the connection and difference between the three body techniques this month.

“…… In general, the stand-in technique is more complex and difficult to learn than the transformation technique and the doppelganger technique. At the same time, because the first two three-body techniques are similar to the stand-in technique, I finally taught you the stand-in technique. With the foreshadowing, it will be easier to master the most difficult stand-in techniques. ”

Chisato raised his hand, got Sugimoto's permission, stood up and asked, "Sugimoto-sensei, I think it seems that the stand-in technique allows us to switch places with the stake, right?" If we could just make the stake look like us, wouldn't it be of much use? ”

Waving his hand for Chisato to sit down, Sugimoto replied, "Of course, the stand-in technique doesn't just make other items look like us. Taking it a step further, Stand-in allows you to swap positions with Stand-in items to hide yourself while avoiding enemy attacks. It's just that you don't have to think about that now, just learn to change the object to your own appearance, so that it can move freely, and learn some techniques for swapping the double with yourself. ”

Looking at the students in the audience who were in a commotion because of this story, Sugimoto reminded them, "It's very difficult to swap places between yourself and the stand-in props, because it already involves the transformation of space. More often than not, ninjas use a rudimentary stand-in technique, as long as they judge the enemy's attack in advance and prepare for it, and the technique is skillful and ingenious, so as not to be discovered, then the effect of the two is the same. ”