Samui could be a great main character. She is a strong and intelligent kunoichi from the Hidden Cloud. Her skills in combat and her calm demeanor would make for an interesting story as she takes on various challenges within the village and outside.
An orphan with no known family could be the main character. They discover they have a hidden bloodline through a series of events. It could be a bloodline that gives them the ability to see the past or future in dreams. This character would then be on a journey to figure out where they came from and what their power means, all while trying to fit into the ninja society.
It could be an original character created by the fanfiction writer. This character could be from a minor clan in the Naruto universe but has extraordinary intelligence and potential.
Sasuke could be a great candidate. He has always been a bit of an enigma, with his brooding nature. He could be hiding a new power or a different side of his personality behind a mask, either self - imposed or as a result of some outside influence. Maybe he's trying to hide his true intentions from Naruto and the others as he pursues his own goals.
It could be a new, original character created specifically for the fanfiction. This character might be an outcast ninja who discovers the Cloud Fusion Sword and uses it to gain respect and power in the Naruto world.
Well, he might learn new ninjutsu specific to the Cloud Village. Their fighting style is different from Konoha's, so Naruto could gain some really powerful lightning - based jutsus. Maybe he'd also form new friendships with Cloud ninja like Killer Bee, and they could team up for some amazing missions.
It could be a new character. For example, a young wizard from a far - off land who comes to Hogwarts specifically to find the hidden blade. He has his own set of skills and knowledge about the blade that no one else at Hogwarts has.
It could be a rogue ninja from another village who wants to use the demon within Naruto for his own evil purposes. He might be power - hungry and sees Naruto as a tool to gain control over the Hidden Leaf and other ninja villages.
It could be Orochimaru. He is always interested in new and powerful weapons. With Naruto having hidden blades, Orochimaru might see it as a threat and try to take the blades for himself, leading to a conflict.
It could be a rogue ninja who was once part of the same clan that the hidden blade belongs to. He wants the blade back to gain ultimate power and is willing to do anything to get it from Naruto.
Rock Lee could be an important ally as well. His unwavering determination and physical strength would be useful for the heavy - lifting tasks involved in building the village, like constructing buildings and fortifications. Also, his positive attitude would inspire the other villagers to work hard towards making the new village a success.