Who could be the main antagonist in a 'naruto covers his face fanfic'?

Perhaps he's trying to protect himself from some kind of danger. There could be an enemy who is looking for him and by covering his face, he can avoid being detected easily. It could also be a part of a new jutsu or power he has discovered where covering his face is necessary for its activation or control.

It could be a new, powerful ninja who has a vendetta against Naruto. This antagonist might be jealous of Naruto's popularity and power, and wants to take over the Hidden Leaf Village.

It could be a new character. Maybe a powerful ninja from a far - off land who has heard rumors of Naruto's strength and is determined to draw it out and defeat him to prove his own superiority. This antagonist might be secretly spying on Naruto and trying to find ways to force him to show his true power.

Maybe Kabuto. He's a sly character who often works for the more powerful villains. He could be sent to capture Naruto's younger self for some experiment or to gain information. Naruto would need to fight against Kabuto's medical ninjutsu and his sneaky tactics to save his younger self.

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.

It could be a rogue ninja who has mastered parkour to an extreme level. He uses his skills to steal important ninja artifacts and Naruto has to stop him. This antagonist would be very fast and agile, making it difficult for Naruto to catch him using normal ninja techniques.

Madara could still be the main antagonist even in a 'naruto bankai fanfic'. He senses Naruto's new power and realizes it could be a threat to his plans of world domination. He adapts his strategies and attacks Naruto with all his might, trying to prevent Naruto from fully mastering and using his Bankai - inspired power to its fullest potential.

A powerful and corrupt ninja from another village could be the main antagonist. He hears about the unique knives in Naruto's village and decides to steal them to increase his own power and the dominance of his village. He would stop at nothing to get his hands on these knives, even if it means starting a war between the villages.

A mysterious figure within Konoha who has a hidden agenda. This person doesn't like the idea of Naruto breaking the norms and wearing a dress. They secretly manipulate events to make Naruto's life difficult while he's in the dress. For example, they might arrange for Naruto to be in situations where his dress - wearing causes maximum embarrassment, all in an attempt to make him conform to the traditional ways.