In a 'naruto goes crazy fanfic', Naruto might start to use his powers in unpredictable and extreme ways. He could go against his usual moral code and attack his friends or allies by mistake, perhaps due to some powerful dark influence or a misunderstanding of a new jutsu he's acquired.
In a 'naruto goes crazy fanfic', it's possible that Naruto's inner demons, like the Nine - Tails' influence, could take over him completely. This could make him act like a wild animal, attacking anyone who comes near him. His friends would then have to find a way to bring him back to his senses, either by using some kind of sealing jutsu or by appealing to his memories and emotions.
Madara Uchiha could be the cause. Even if he's dead, his influence could still be around. Maybe he left behind some sort of genjutsu or curse that affects Naruto's mind and drives him crazy. After all, Madara was always planning something big and Naruto would be a great pawn if he's out of control.
In the 'naruto goes to amegakure fanfic', Naruto might encounter new and powerful ninja. He could learn unique jutsu specific to Amegakure. Maybe he'll make new friends or face off against some hidden enemies there.
In the 'naruto goes to kumo fanfic', Naruto could be on a mission in Kumo. He might make new friends or enemies. He could also learn new jutsu from the ninjas in Kumo. It could be a great opportunity for him to grow as a ninja and expand his understanding of the ninja world.
Perhaps Naruto goes to Orochimaru in an attempt to redeem him. Naruto has a strong belief in the good in people, and he might think that he can convince Orochimaru to stop his evil ways. He could offer Orochimaru a chance at redemption, like a new start in the Hidden Leaf Village if he gives up his dark experiments and ambitions. This would lead to a complex relationship development between them, with Orochimaru being skeptical at first but gradually considering Naruto's offer.
In a 'naruto goes berserk fanfic', Naruto might lose control of his chakra in a new and extreme way. Maybe he's pushed to the edge by a powerful enemy that he can't defeat with his normal strength.
Well, in the 'naruto goes to ame fanfic', Naruto might encounter new and dangerous enemies in the Hidden Rain Village. He could also meet some interesting characters that are unique to this fan - made story. Maybe he'll discover some hidden secrets about the village or its people.
Maybe Naruto will encounter new types of ninjas in the North. He could learn unique jutsu or skills that are specific to that region.
Perhaps he has a mental breakdown due to the stress of his job. He could start yelling at people on the street, thinking they are the cause of all the mess he has to deal with every day. He might even try to chase after those who litter in a fit of rage.
Well, Naruto might be looking for some special ninja tools in Tenten's shop. Maybe he's on a mission and needs something specific, like a new set of shuriken.
In the fanfic, Goku could become friends with Naruto easily. Since they both have a strong sense of justice and a will to protect their friends. Goku might teach Naruto some of his training methods, like training under heavy gravity. And Naruto could show Goku the unique aspects of ninja villages and how they function.