In this fanfiction, a plotline could be Naruto faking his own death to carry out his plans in secrecy. Aizen faked his own death to further his goals, and Naruto could do the same. He could then re - emerge in a new form or identity and start to cause chaos in the ninja world. He would play different groups against each other, using his intelligence and charm to manipulate the situation. As he does this, some of his friends might start to suspect that he is not really dead and begin to investigate, leading to a series of tense encounters and revelations.
A plotline might involve Naruto secretly building an army of his own, much like Aizen did with the Arrancar. He could be recruiting powerful ninja from different villages under false pretenses. He would act friendly and trustworthy on the surface, but in reality, he is using these ninja for his own grand scheme. Also, Naruto could start to experiment with dark jutsu, similar to how Aizen experimented with Hollowfication, all while hiding his actions from his former allies.
One possible plotline could be Naruto starting to manipulate the political situation in the ninja world. Just as Aizen had his own designs on the Soul Society, Naruto could use his influence to create power imbalances among the ninja villages for his own gain. Another could be Naruto using his new - found Aizen - like charm to deceive his friends into following a path that they don't fully understand. He might make them believe that he is still the same Naruto, but his actions would be leading them astray.
One possible plotline could be Naruto getting some of Kaneki's ghoul - like powers. So he has to deal with the hunger for human flesh in a way that's similar to Kaneki's struggle, but in the Naruto universe. Maybe he tries to resist it while still protecting his village.
Maybe there's a plot where Naruto is influenced by an external force that makes him act like the Joker. He then starts to target the powerful figures in the ninja world, not to defeat them in a traditional sense, but to expose their weaknesses and make them look foolish, just like the Joker does with Batman. And as he does this, his relationships with everyone around him start to crumble.
One plotline could be Naruto getting involved in underground ninja activities like Zabuza used to. He might take on assassination - like missions in the shadows, which would put him at odds with the Leaf Village's more ethical code. Another could be his old friends trying to bring back the real Naruto. They would set out on a journey to find out what made him change and how to reverse it. Also, he could form an unlikely alliance with some of Zabuza's former associates who recognize his new behavior and see an opportunity to use him for their own gains.
One possible plotline could be that Naruto's dad, who is an Aizen fan, tries to incorporate some of Aizen's leadership or strategic thinking into his own actions in the Naruto world. Maybe he uses Aizen - like deception in battles but for good purposes, like fooling the enemy to protect the village.
One possible plot development could be that Harry begins to undermine the existing power structures at Hogwarts. He might start by sowing seeds of doubt among the students and teachers, just like Aizen did in his own world. Another could be that he forms a secret group of followers who are loyal to him and his new ideals.
One plotline could be Naruto going on a journey to write a book about the ninja world, just like Jiraiya did. Another could be Naruto using Jiraiya's flirting techniques on Sakura, which would create a lot of comical and awkward situations. Maybe Naruto starts his own toad - summoning school, inspired by Jiraiya's connection with the toads.
One possible plotline could be that Harry starts to show an interest in dark magic like Tom Riddle did. Maybe he becomes overly ambitious in his studies, trying to outperform everyone in a way that borders on the obsessive competitiveness that Riddle had. Another could be that Harry begins to isolate himself from his friends, just as Riddle did when he was at Hogwarts, as he delves deeper into the knowledge that Riddle once pursued.
One possible plot twist could be that Naruto's friends think he's been possessed or something. They would try to find a way to bring the old Naruto back. Another could be that Naruto's new attitude actually makes him a more powerful ninja, which causes some jealousy among his peers.
One possible plot could be that Naruto, for some reason, decides to adopt Sasori's more calculating and detached approach to combat. He might start using puppets or puppet - like techniques in battles, much like Sasori did. Maybe he's on a mission where he has to infiltrate an enemy base and he thinks acting like Sasori would be the best way to succeed.
One possible plot development could be Naruto getting into more intense battles with stronger opponents. Since Kenpachi is always seeking strong battles, Naruto may start to do the same. This could lead to him exploring new areas to find worthy foes.