Perhaps in a fanfiction, Naruto's Four Tails form could be the result of a new experiment gone wrong. And as he tries to reverse the effects, he discovers new powers and abilities that come with this form. He could also meet other characters who have similar 'altered' forms and together they could form a special team to protect the village. This would add a whole new layer of complexity and friendship dynamics to the story.
Naruto could use his Four Tails form to fight a new and powerful enemy that the normal ninja of the Hidden Leaf can't handle. For example, an enemy with the ability to nullify regular chakra attacks.
One idea could be a story where Naruto has more control over his Four Tails form earlier than in the original series. He could use it to protect the Hidden Leaf in a new and unexpected way, perhaps by combining it with some new jutsu he's created on his own.
Another possibility is that Naruto's sickness is a sign of a greater imbalance in the chakra world. The Nine - Tails, being a powerful source of chakra, could be at the center of this imbalance. So, the story could revolve around Naruto and his friends trying to restore the balance while also taking care of Naruto's health. This would involve a lot of exploration of the Naruto universe's lore and the relationship between different chakra entities.
Well, Boruto might be really shocked. He has seen Naruto in his normal state, but seeing Naruto in the 4 - tails form through a fanfiction would be wild. He might be amazed at the power his father once had to control such a powerful and wild form. He could also start to understand more about Naruto's past struggles.
Kabuto could also be a good antagonist. After he gained all those powers and knowledge, he might target Naruto's six - tails form. He could use his medical ninjutsu to try and manipulate Naruto's transformation or even try to extract the power of the six - tails for his own use. Since he has the ability to mimic other ninja's techniques, he could be a formidable foe against Naruto in six - tails form.
In the 'Naruto Gets the Juubi Ten - Tails Eye' fanfiction, there are many possibilities. Naruto may use the eye's power to heal the wounds of the ninja world, both physical and emotional. He could use it to restore damaged lands and revive extinct species. Politically, he could use his new - found power to unite the various ninja villages in a way that has never been done before. His influence would spread far and wide, and he could become a symbol of hope and change, not just for the ninja world, but for all the realms that are somehow connected to it.
Well, one possibility is that Naruto's fighting style might change. The Sound Four have their own unique jutsu and combat techniques. If Naruto joins them, he could learn some of those, like how to better use sound - based attacks perhaps. He might also become more stealthy as the Sound Four are often involved in sneaky operations.
Well, if Naruto joins the Sound Four in fanfiction, it could lead to a complete change in the story's dynamic. Naruto's positive and determined attitude might influence the Sound Four to question their loyalty to Orochimaru. Maybe they would start to see a different path, one that doesn't involve all the dark and evil deeds Orochimaru has planned.
Well, in 'tails becomes paralysed fanfiction', it could lead to a story of Tails' inner strength. Despite being paralysed, he could start to explore new ways of using his intelligence. Maybe he invents some special devices to help him move or interact with the world again, showing his resilience.
In such a fanfiction, Tails might be kidnapped by an old enemy like Dr. Eggman. His friends, like Sonic, would then start a rescue mission. They would search all over the place, from the Green Hill Zone to Eggman's secret bases.
If the Ten - Tails Jinchuuriki travels through time in Naruto, they could change the fates of many characters. For example, they might save characters who were supposed to die, like some of the Uchiha clan members. This would have a huge impact on Sasuke's story and the overall plot related to the Uchiha. It could also lead to different alliances forming as the power balance in the ninja world shifts due to the presence of this extremely powerful being.