The sword might be a tool for Naruto to better understand his own heritage. For example, it could be linked to his Uzumaki clan in some way. He might discover that the sword was created by an Uzumaki ancestor to combat a specific threat that is now resurfacing. This would lead to Naruto delving deeper into his clan's history and unlocking new powers or techniques related to it. Also, the sword could attract unwanted attention from enemies who either fear its power or want it for themselves, forcing Naruto into new and dangerous battles.
One possible plot twist could be that Naruto gains the Mangekyou Sharingan in a moment of extreme emotional turmoil, like seeing Sasuke in a life - threatening situation. This new power might make him an outcast in Konoha at first, as the Sharingan is a symbol of the Uchiha. Another twist could be that the Mangekyou Sharingan has some unforeseen side effects on Naruto's chakra system, making it difficult for him to control his normal jutsu. It could also lead to a power struggle within the village as some might fear Naruto's new - found power.
One exciting plot twist could be that Naruto's new bloodline gives him the ability to control time. He could then use this power to go back and prevent some of the tragedies in the Naruto world, like the Uchiha massacre. Another possibility is that the bloodline makes him immune to all genjutsu, which would completely change his battles against opponents like Itachi or Madara.
The Jiongu could have a connection to Naruto's family that he was unaware of. Maybe it was something that his ancestors had encountered before. This discovery could change his perception of his family's history. Also, the Jiongu might seem like a great power at first, but it could turn out to be a double - edged sword. It could start to drain Naruto's life force or chakra over time, forcing him to find a way to either get rid of it or find a balance.
One possible plot twist could be that Naruto's parents were actually alive all along and in hiding. Danzo took Naruto to use him as a bargaining chip against them later. Another could be that Danzo believed Naruto had some special power within him from birth that he wanted to control for the village's 'greater good'. Maybe Naruto's parents knew about this impending threat from Danzo and had a secret plan in place for Naruto to overcome it.
One possible plot could be that Naruto discovers a magical sword. This sword might have special powers like being able to cut through any jutsu. He then has to learn how to master it, which could involve going on a journey to find an old hermit who once used the sword. Along the way, he faces challenges from enemies who also want the sword for their own evil purposes.
Well, one plot twist could be that Thor has to return to Asgard suddenly for some emergency, leaving Jane alone on Earth while pregnant. This would create a lot of emotional turmoil for her as she has to deal with the pregnancy without him.
The 'Gohan gets revealed as Saiyaman fanfic' could have a plot twist where Gohan is forced to reveal his identity to save someone. Say a villain has captured Videl, the girl he has feelings for, and the only way to rescue her is by showing his true self as Saiyaman. This would not only expose his identity but also his feelings for Videl. Another plot twist could be that Gohan's Saiyaman identity is actually a clone created by an enemy. So when the real Gohan shows up at the same time as Saiyaman, it causes mass confusion. And finally, it could be that Gohan's reveal as Saiyaman leads to a new form of training for him. Since his identity is out in the open, he has to learn to fight without the disguise and in a more public way, which forces him to develop new techniques and powers.
One plot twist could be that the person who cheated on Naruto actually has a very good reason, like they were forced to do it to protect Naruto from a greater threat. Another could be that in ANBU, Naruto discovers that the cheating incident was part of a larger conspiracy against him. Maybe his new ANBU teammates turn out to be related to the cheater in some way, creating a lot of internal conflict for Naruto.
In a Naruto Gets Odin's Eye fanfiction, there could be a plot where Naruto's world is somehow merged with the world of Norse mythology. The acquisition of Odin's eye could be a key factor in this merge. Naruto could use the eye to communicate with the Norse gods and gain their support in battles against his foes. This could also introduce new villains from Norse mythology. His friends in Konoha would be both amazed and a bit intimidated by his new power. Naruto would have to learn to control the power of Odin's eye quickly to prevent it from causing chaos in his village.
Well, it could be about Naruto getting into some serious trouble in the Hidden Leaf Village. Maybe he broke an important rule or made a big mistake during a mission. And as a form of punishment, he gets spanked by one of the village elders or his sensei. It's a rather unorthodox way of discipline in the Naruto world but could make for an interesting fanfic plot.