Shinobi World's Modern Guest.

The rasengan.

Jiraya showed Naruto the first step of the rasengan, which was to pop a balloon. The sage didn't tell the blonde the secret of how to pop it, but he showed how he did it atleast.

The sage held the balloon in his hand as it bubbled before popping, spraying water all over the grass. It was difficult for many because they couldn't figure out it's "Secret", but our protagonist knew it's secret. It was rotation, after the user puts enough rotation in it with Thier chakra, it would pop. And when done from multiple directions it would spray water all over like Jiraya's.

After a week of being in this world, Naruto had figured out something. Like how our hairline is tired in one way and our fingerprint's rotate in another way, it's either one of those patterns that the chakra tenketsu are placed or a balanced placement. For example, if you have clockwise direction hairline and anti clockwise finger print pattern, then your chakra tenketsu are in a balanced position, where they have freedom to go anywhere. This wasn't a problem in many ninja techniques but when it came to the rasengan, the balanced position was the best. Lucky for Naruto, he had the balanced tenketsu in his body.

Naruto took advantage of that fact and started to rotate his chakra into the ball, one small step at a time. After a while hour, he was finally able to create a small hole.

[Rasengan- Rotation learnt.

Rotation- Level 1 1%]

Naruto made three shadow clones that helped him master it quickly, If he wanted a perfect rasengan, then he must practice this step until he masters it.

After fives minutes a new batch of clones appeared, dispelling the old batch. The Uzumaki received the experience gained from his shadow clones, which was about 15 minutes of experience.

[Rotation- Level 6 9%]

Naruto sighed, this was going to take a long time, but atleast it was better than doing nothing. He created another batch if 20 shadow clones to practice chakra enhancement and another 20 to practice hies taijutsu prediction technique.

[Rotation- Level Max]

It took him half a day but he finally did it, he had mastered rotation step of the rasengan. If he remembered correctly then the canon Naruto did his in a couple of days but even he didn't fully master it. So it was an improvement to canon and the Reincarnated Uzumaki felt himself improving.

An hour later Jiraya returned, he was casually strolling down the training ground, expecting the blonde to be rolling all over the ground in frustration. But he saw 50 shadow clones duking it out, doing a battle royale type spar. He watched as a shadow clone dispelled another, and that clone being dispelled by the real Naruto. Until only the real one remained.

"That was impressive gaki, but it's too early to give up on the rasengan." Jiraya commented, expecting the Uzumaki to be motivated into completing the first step, but instead said Uzumaki pulled out another water balloon. The chakra swirled around as a whirlpool formed inside the ball, making it unstable and collapsing the balloon, spraying water over Jiraya's shocked face.

"I-impossible, it took me two weeks to do that." Jiray said with a stutter, Jiraya was seriously shocked, this amount of prodigious talent was unseen. He was unsure if even the likes of Hashirama and Madara could compare to The Uzumaki. He was sure this time, this child was the child if prophecy.

"You gonna teach me the next step or stare into my face?"