I am not a knight, reborn as an old sword

Next, Tsunade took Liuyun to the room alone and began to teach him the Yin Seal Ninjutsu.

Because this is a forbidden technique, Tsunade must teach him step by step to be sure, so this time Liuyun did not fully use the system's training function, but only occasionally assisted to speed up understanding and application.

Even so, the progress of learning was enough to shock Tsunade. In just half a month, Liuyun understood the principles of the Yin Seal.

Only after fully understanding it, Liuyun finally understood why the Yin Seal was called the Yin Seal, not the Yang Seal.

Because the premise of the Yin Seal is that you must master a large amount of Yang attribute chakra.

And to seal the Yang attribute chakra in the mark on the forehead, you must use an opposite force, that is, the Yin attribute.

And this kind of seal is a kind of Yin attribute change, and its ability is only one, which is to seal the Yang attribute power.

And the chakra stored in the mark on Tsunade's forehead is not ordinary chakra, but some Yang attribute chakra.

Only Yang attribute chakra can be stored in the Yin Seal.

When using it, as long as the Yin seal is unlocked, a large amount of Yang attribute chakra will flow out, which can be used for treatment, for self-physical skills, etc.

After Liuyun learned the Yin seal, a diamond-shaped mark immediately formed on his forehead.

It's just that he hasn't stored much Yang attribute chakra in it yet.

"This is definitely a powerful forbidden technique!"Liu Yun couldn't help but sigh as he tried to store the Yang attribute chakra that he had condensed into the mark on his forehead bit by bit.

At this time, Tsunade said again:"Although the Yin Seal has been formed, it also has to be used in conjunction with its method of application, the Creation Regeneration and the Hundred Healings Technique!"

Liuyun nodded.

He naturally knew the two ninjutsu that came with the Yin Seal. Creation and regeneration was a purely medical application that could keep one from dying in battle.

Of course, this so-called immortality was only relative.

As long as one was not instantly destroyed or suffered soul-level damage, one could basically be considered immortal.

For Liuyun and Tsunade, there were few people in the ninja world who could hurt such strong men as them to that extent.

So they could indeed be called immortal.

The Hundred Healings Technique was more inclined to use Yang attributes to strengthen physical skills and body energy. It not only had strong recovery power, but also had additional powerful strength.

With this forbidden technique, Liuyun had added another big trump card.

Moreover, Liuyun's thoughts spread out, considering whether other seals could be studied through the principles of the Yin Seal.

For example, Yang Seal?

For example, Fire Seal? Water Seal? Thunder Seal and the like?

Perhaps, he really had to study the sealing technique. He felt that there was a lot of knowledge to be studied in the sealing technique!

"Now I finally understand why the Uzumaki clan was destroyed."Liuyun couldn't help but think.

Liuyun stayed in the town for about a month and thoroughly mastered the two supporting functions of the Yin Seal.

By now, more than two months had passed since he left Konoha Village to investigate Orochimaru's mission. In these two months, he also drew prizes twice, but unfortunately, he didn't draw anything good.

He thought that if he could draw a treasure like the Life Essence again, he must keep it for Tsunade to repay her kindness.

Although Tsunade is a member of the Senju clan, she has strong vitality and a very long life, but her body is actually overdrawn a lot when she constantly uses creation and regeneration. Although her life span will not be shorter than that of ordinary people in the end, it will definitely not be much longer. The

Life Essence can replenish a person's lost vitality, that is, it can increase the upper limit of a person's cell division. For Tsunade, this is definitely a real treasure.

Before, Liuyun was not strong enough, so he naturally had to keep it for himself. Now even if he takes more Life Essence, it will not have much effect. If he can draw it, of course it is best to give it to Tsunade.

PS: The second update is here!!!! I beg for everything!!!