Who could be the main antagonist in 'naruto has a hidden bloodline fanfic'?

It could be a rogue ninja who also has a rare bloodline and sees Naruto as a threat to his own power and status. This antagonist might want to steal Naruto's bloodline or simply eliminate him to be the only one with such a special ability.

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.

Another possibility is that the antagonist could be a dark - side version of Naruto himself. The discovery of the forgotten bloodline could stir some dark desires within him. This internal struggle could be personified as a separate entity that tries to take over Naruto and use the power of the bloodline for evil. Naruto would then have to fight against this internal darkness as well as external threats who are also interested in his new - found power.

It could be a rogue ninja from the Hidden Leaf's past who has come back for revenge. Maybe someone who was wronged by the village long ago and has now amassed great power to destroy it. Another possibility is a new enemy from outside the village, like a powerful warlord from a far - off land who wants to conquer the Hidden Leaf for its resources.

It could be a powerful rogue ninja who has a vendetta against Naruto specifically because of the gunblade. Maybe he was once part of a group that was tasked with protecting the gunblade, but it was lost under his watch, and he blames Naruto for having it now.

It could be someone who wants to steal the One for All bloodline from Naruto. Maybe a rogue ninja from another village who has heard about this new and powerful ability in Naruto and decides to make it his own.

Maybe an ancient evil spirit that was sealed away long ago but is awakened by the emergence of the Adamantium bloodline. This spirit believes that the power of the bloodline can be used to break free from its final seals and wreak havoc on the world.

One interesting plot could be that Naruto discovers his hidden bloodline gives him the ability to control time in small increments. This allows him to dodge attacks more easily and plan his counter - attacks more effectively.

It could be Orochimaru. He's always been interested in unique powers and abilities. The idea of X - 23's mutant abilities and Naruto's jinchuriki powers would be very appealing to him. He might try to capture them both to use in his experiments to gain ultimate power.

A new character could be created as the antagonist. For example, an Uchiha who has been corrupted by the power of the Sharingan and wants to use Naruto's special Uchiha - related abilities for his own evil purposes. This character could be jealous of Naruto's unique position within the Uchiha - related story and try to take it from him.