WARNING: The following contains spoilers for Boruto: Naruto Next Generations Episode 171, "The Results of Training," now streaming on Crunchyroll.
In the Boruto series, both the anime and manga, Naruto's son has been desperate to surpass his father's prowess in battle. However, it's no longer out of some petty rivalry or insolence, but because Boruto knows the better he is, the easier he'll make Naruto's job as the Hokage of Konoha.
It's why he's so broken that he and Team 7 couldn't take Deepa out recently when he stole the Hashirama Cell. The whipping left Mitsuki near death but it pushed a weakened Sarada to train with Sasuke, and now, Boruto is trying to level-up with Kakashi. And in Episode 171, he makes giant strides as his new Rasengan turns out to be way more powerful than expected.
Boruto's Wind Style Rasengan couldn't pierce Deepa's metallic body so he's trying to create one that could top what his predecessors, such as Naruto, Minato (Boruto's grandfather) and Naruto's trainer, Jiraiya, achieved. It's why Kakashi wants him to fight the vicious cannibal Shojoji as it's way better than testing the move out on some boulders. Thanks to Shikadai, Boruto thinks he knows how to manipulate the chakra bomb and so, Kakashi sanctions the brawl after bringing the prisoner to a military facility.
What happens next is a total slugfest with Shojoji trying desperately to eat Boruto. He has it in for the kid after Boruto helped stop the Mujina Bandits. Thankfully, despite the big man's speed and knowledge of how Boruto will attack, the young shinobi still ends up being unpredictable. This creates an opening for him to apply his Rasengans, although the first one is blocked by Shojoji's wind-shield and sent to the roof. But while the tyrant thinks Boruto's not strong enough, he's really just testing Shojoji's defenses.
Boruto decides to use the High Compression Rasengan. Rather than trying to make it as big as possible, he condenses all the energy into a smaller one that pushes it past its chakra limits. Basically, it's a little nuclear nugget and as he forces it through, Shojoji's shield can't block it, throwing him through the wall. Kakashi's stunned, admitting it's stronger than his own, as well as a move more powerful than what other wielders could do at that age.
If Shojoji didn't have that shield, Kakashi supposes he'd be dead. Boruto passes out, however, as it drains his body. Once he can manage his levels and manipulate his chakra nature better, this Rasengan would become an even deadlier weapon.
After all, he can already turn it invisible, so once it doesn't take such a toll on his body, and should Boruto use Kakashi and Naruto's expertise, as well as intel from another Rasengan-user in Konohamaru, he may become the best wielder ever. Kakashi senses this, standing in awe how brilliant this new generation is, and while he won't say it to his face, he knows Boruto's has the potential to be better than his father.
