Well, when Naruto and Jiraiya's jutsu goes wrong, it could lead to a disruption in the space - time continuum within the fanfiction world. Jiraiya might be sent to a different dimension while Naruto is left behind, and they have to find a way to reunite. This could involve Naruto having to learn new jutsu to open a portal to the dimension Jiraiya is trapped in. It would be a long and arduous journey for Naruto, full of self - discovery and growth as he tries to save his mentor.
The story could develop with Naruto and Jiraiya having to face the consequences of their failed jutsu. Maybe they are shunned by the village at first because of the danger they pose.
In fanfiction, when Naruto goes to the library, he might discover a hidden jutsu scroll. Maybe it's a long - forgotten technique that could give him an edge in battles.
In fanfiction, when Naruto goes to the hospital, he could discover a new medical jutsu being developed there. He might get involved in the process, either by accident or because the doctors need his help. Since he has so much chakra, it could be useful for testing or something related to the new jutsu.
In fanfiction, Naruto might discover hidden jutsu in Uzushiogakure. Maybe he finds ancient scrolls that hold the secrets of powerful water - based techniques since Uzushiogakure was known for its water - style ninjutsu.
One thing that could happen is that Naruto would learn a lot more about the toad sage mode earlier. Jiraiya could start training him right away. This would give Naruto an edge in battles. He would be able to use the toad - related jutsu more effectively and have a different combat style.
He could become even more powerful. The Vacuum Jutsu might allow him to defeat stronger enemies more easily.
Well, he could become extremely powerful. Maybe he'd use the forbidden jutsu to defeat powerful enemies like Madara or Kaguya in a really unexpected way. For example, if it was a time - travel related jutsu, he could go back in time and stop certain events from happening that led to the rise of these villains in the first place.
In a fanfiction where Naruto gets adopted by Jiraiya, Naruto's training would be intense and unique. Jiraiya has a lot of unorthodox methods. He could introduce Naruto to some very special and secretive forms of chakra control. Naruto might also learn more about the secrets of the Sage Mode much earlier. With Jiraiya's guidance, Naruto could form stronger bonds with other powerful ninjas that Jiraiya knew. This would give Naruto more allies and a greater understanding of the political and power dynamics in the ninja world.
In this fanfiction, Jiraiya might also take Naruto on some adventures. They could go on a journey to explore some hidden places in the Naruto world. Along the way, Naruto would learn not only about combat skills but also about different cultures and histories within the world, which would shape his character in new and interesting ways.
Well, Naruto with the Rinnegan trained by Jiraiya would be extremely powerful. Jiraiya could teach Naruto unique ways to use the Rinnegan's abilities. Maybe Naruto would combine Sage Mode with the Rinnegan powers, creating new and unbeatable jutsu. He could also use the Rinnegan's ability to see chakra flow to better understand his opponents and counter their attacks more effectively.