Currently Rey was standing in a forest in the land of toads and beside him were many water filled balloons and rubber balls on the ground. He had decided to come here as he didn't want anyone to disturb him or see what he was doing and ask him where he learned it, but he would always go back home in the night to spend some quality time with his lovely partner. 

He had finally decided to focus on learning the Rasengan by himself, he could have asked Konohamuru to teach him, but after thinking about it, he decided not to.

Rey already knew about the procedure based on his knowledge from previous life, as he had tried to perform it in his previous life.

By learning it himself, not only would he have a better understanding of chakra transformation by trail and error method, he would also have a great increase in his reputation among the higher ups.

Rey had five of his clones focusing on learning all the stuff provided by Sakura as soon as possible, while two more were trying to learn the Rasengan alongside him.

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Rey picked up a water balloon and injected chakra into in, making the water inside to start spinning in a clockwise manner on its own.

' The first step is learning to spin the chakra in multiple directions at once. ' Rey thought and then alongside the two shadow clones started practicing. 

Initially Rey tried to just move his chakra in random directions, but the balloon didn't burst, Then after failing for multiple times, he changed his approach and started moving his chakra in different direction in different layers.

He created thin layers of chakra rotating in different directions placed above each other, so that they won't hinder the flow of each other.

And the balloon burst immediately just as he used that approach.

For the next three days Rey's routine was to wake up, have a lovely heated session with Tenten and when she left for the shop he would to Mount Myoboku to start practicing the Rasengan again. He would return when it was time for Tenten to come back, then they would cook together, eat together and after another long heated session, sleep while cuddling each other.

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On the first day Rey had already started to practice with the rubber balloon, but he didn't move onto the second step, which included using more and denser chakra to burst the rubber balloon.

He tried to create as many layers of differently rotating chakra as possible in the rubber balloon as the water balloon would burst before he could do so.

He found out that after a certain number of layers, the initial layers would lose their shape as he would lose concentration due to having so many of them.

Rey then used his shadow clones to create more layers above his layers when he reached his limit and to his surprise the rubber balloon also burst after reaching a certain number of layers.

Only then did he move to the second step which took him half a day to burst the rubber balloon, but he continued to test his limit with a bigger and stronger rubber balloon.

The absolute chakra control skill helped him a lot throughout the process and finally it was time for the final step.

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The final step was to create a spherical container of chakra to contain the first two steps inside.

For this Rey used a simple air filled balloon and tried to create a dense layer of chakra surrounding in without moving the balloon. 

Finally, after reaching his limit in all the three steps he decided to try to create a Rasengan.

Under Rey's command, the shadow clone first tried to create a smaller Rasengan with less chakra and succeeded on the first try.

But when he tried to create it to his maximum limit, the dense spherical layer outside wasn't strong enough to hold the destructive power inside and broke down, tearing the shadow clone into shreds and leaving a two feet wide crater on the ground.

Rey once again used a shadow clone to try it out, but the result remained the same.

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The outer shell of chakra would stay strong when the shadow clone limited the chakra and layers of rotation inside it, but upon doing it to the maximum limit, the shell would break down due to the immense pressure inside.

Rey found two solutions to that problem, One was to use another shadow clone like Naruto to help him strengthen the outer shell, Another was to make the shell bigger in size to decrease the pressure inside.

The problem with second solution was that it would decrease the destructive power due to it focusing on a relatively larger area.

Rey was testing those Rasengan on a giant boulder to see the results. When he used the strongest Rasengan he could do by himself, he could create a hole of about 1 feet deep into the solid rock, but when he used two shadow clones, one to make the outer shell, another to supply the chakra while he created rotating layer, he could create a hole of about 5 feet in the solid rock.

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Rey kept the Rasengan as small as possible because he wanted to aim for the maximum destructive prowess, he knew that the results were pretty amazing because the rock was obviously stronger than a human body.

He also didn't need to worry about chakra because he finally got 100% of Tenten's chakra and had reached Elite Jonin level according to the system, approximately 20 times more than his initial chakra capacity. 

He could now stay in the sage mode for five minutes and fifteen seconds, which crossed the so called limit of five minutes, making him come to the conclusion that either his limit was greater or that restriction didn't apply to him and he could stay in the sage mode as long as he had enough chakra.

Rey also tried different things which the newly acquired chakra as he powered up his lightning bolt with all his senjutsu chakra while in sage mode and threw it on the giant Boulder, making around a 10 feet deep hole inside it.

However, In sage mode he could use all his senjutsu chakra to create a Rasengan by himself, which was almost 2 feet in diameter even in the most concentrated form Rey could perform, that Rasengan pierced through the almost 20 feet wide boulder, causing a wide proud smile to appear on Rey's face.

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