Who could be the main antagonist in a 'naruto joins hunter nin fanfiction'?

One possible plot could be that Naruto, seeking new challenges and ways to grow stronger, decides to join the hunter nin. He might bring his unique ninja skills from Konoha, like his shadow clones. His positive attitude could start to change the somewhat secretive and often dark hunter nin culture. He could also make new friends and enemies within the hunter nin ranks.

Danzo could be a great antagonist. He always had his own secretive and often unethical plans. He might see Naruto as a threat even if he's innocent and frame him as a missing - nin to get rid of him.

Perhaps an old enemy of one of the members of Team 9 shows up. Since Naruto has joined the team, they might see it as an opportunity to get revenge. This antagonist could be someone who was once defeated by the member's family and now wants to prove themselves. They would be very cunning and use their knowledge of the team member's past to try and divide the team.

It could be an old enemy who has resurfaced, like Orochimaru again. Since Naruto and Sasuke are together now, Orochimaru might see them as a threat to his own plans for power and immortality.

It could be the leader of the dark guild. This person would likely have a very different ideology from Naruto's. Maybe the leader believes in using extreme and unethical means to gain power, like sacrificing innocent lives for dark magic. Naruto would constantly clash with this leader as he tries to uphold his own values.

Orochimaru could still be the main antagonist. Even if Naruto joins Team Hebi, Orochimaru's motives are often self - serving and evil. He might be using the team for his own experiments or to gain power, and Naruto would oppose that. Naruto's presence in the team could disrupt Orochimaru's plans, leading to a conflict between them.

Orochimaru would likely be a main antagonist even if Naruto joins the Sound Village. Orochimaru has his own devious plans, and Naruto might not fully agree with them. Even though Naruto is in the village, Orochimaru could try to use Naruto for his own gain, like getting access to the Nine - Tails' power. So, Naruto would constantly be at odds with Orochimaru.

Maybe a female ninja who has been secretly training to become a Hunter Nin. She could break the gender stereotypes in the Naruto universe and show that female ninjas can be just as effective, if not more, as male Hunter Nins. She could have her own unique set of skills and a strong motivation for becoming a Hunter Nin, like avenging her family who were killed by a rogue ninja.

It could be a powerful devil who has the ability to control minds. This devil could manipulate some of Naruto's friends and turn them against him, creating a lot of internal conflict within Konoha.

The main antagonist could be Madara. Even though Obito was once following Madara's plan, with Naruto joining Obito, Madara might see this as a threat to his grand scheme. He could try to manipulate events to drive a wedge between Naruto and Obito or directly attack them to stop their new alliance from achieving their goals.