Perhaps in some fanfictions, the past reveals that there was a secret alliance between the Leaf Village and an enemy village long ago. And in the future part of the fanfic, this alliance resurfaces and creates a whole new dynamic among the characters. It might lead to Naruto having to make difficult choices between loyalty to his own village and this newfound connection.
A really interesting plot twist could be that Naruto's past encounters with certain characters were actually manipulated by a time - traveling villain. As he reads into the future in the fanfiction, he has to figure out how to break free from this pre - set path and create a new future for himself and the ninja world.
One of the most interesting plot twists could be that Naruto discovers a new form of chakra that has the power to rewrite history. This would completely change the power dynamics in the Naruto universe.
A really interesting plot twist could be around the Half - Blood Prince himself. The fanfiction could explore the idea that the identity of the Half - Blood Prince was misinterpreted in the original book. Maybe it was a red herring, and there was someone else who was the true 'Half - Blood Prince' all along, with a completely different set of motives and actions that would have a major impact on the story.
Well, a really cool plot twist might be if the main characters from Naruto are suddenly thrust into the world of Shadow of War. Imagine Naruto and Sasuke having to fight alongside the forces in Shadow of War against an even greater evil. Or perhaps a twist where the tailed beasts in Naruto are somehow connected to the dark magic in Shadow of War, leading to a whole new set of challenges for Naruto and his friends.
Well, sometimes in these fanfictions, the reborn Ultron might find out that it was created with a hidden purpose by an even more shadowy figure. This discovery could lead it on a journey to uncover the truth about its origin, and along the way, it has to decide whether to continue its vendetta against the Avengers or not. It's really interesting to see how the writers play with this concept of self - discovery.
One possible plot twist could be Naruto changing the past in a way that completely alters the future relationships. For example, if he prevents a certain event that led to a character's death, it could change the whole dynamic among the characters. Another twist could be that Naruto discovers that the past is not as simple as he thought, and there are hidden forces at work that he didn't know about in his original timeline.
Well, one of the most interesting plot twists could be a character that was thought to be on the side of the humans actually being a secret agent for the Titans all along. This would completely change the dynamic of the story and the relationships between the characters.
Well, perhaps a major plot twist could be that the CCG (Commission of Counter Ghoul), which is supposed to be against ghouls, has been secretly working with some ghouls for their own ulterior motives. This would be a huge shock as it goes against everything they are known for. Also, there could be a twist where a ghoul's kagune (their weapon - like organ) mutates in a way that gives them an unexpected advantage or disadvantage.
A really cool plot twist in Hermione as a Marauders' daughter fanfictions is when she realizes that her real mother was a powerful witch who was erased from history by some dark force. This makes her quest not only about finding her place as the Marauders' daughter but also about restoring her mother's name. Another plot twist could be that the Marauders had some sort of magical pact that is now passed on to Hermione. This pact might force her to make difficult choices between her loyalty to her new - found family and her friends. And sometimes, there's a plot twist where Hermione discovers that she has a twin sister who was separated from her at birth, and this sister has been living in the shadows, also with a connection to the Marauders, which throws a whole new set of challenges her way.
One interesting plot twist could be that Naruto starts to have memories of Tobirama's past battles. This would make him question his own identity and purpose. Another could be that Tobirama's reincarnation in Naruto causes a shift in the power dynamics among the villages. It might make other villages see Konoha as a greater threat or as a source of new knowledge.
One interesting plot twist is that the chakra seal on Naruto is actually a key to an ancient power source. At first, it seems like a hindrance, but as the story progresses, it's revealed that the seal was placed there to protect this power until Naruto was ready. This flips the whole concept of the chakra seal from a negative to a positive in an unexpected way. Also, there could be a plot twist where the sealing of Naruto's chakra was a misdirect, and it was actually someone else's chakra that was being targeted, and Naruto was just a decoy.