Maybe a new character entirely. Someone who has a unique jutsu or ability. For example, a ninja who can control shadows in a different way than Shikamaru. This new character could bring fresh ideas and storylines to the fanfic as the ANBU captain.
Kakashi could be a great choice. He has the skills, experience, and a mysterious side to him that would fit well as an ANBU captain.
There's also a chance that the main character could be a completely new character from a minor clan in the Naruto universe. This character could have some hidden bloodline limit that makes them a prodigy in the ANBU. They might start as an underdog but quickly rise through the ranks due to their exceptional skills and intelligence.
Naruto's character would likely become more serious and focused. As an ANBU captain, he has a lot of responsibility. His godlike powers might make him a bit more reserved as he realizes how much more powerful he is than others. He would also become more strategic in his thinking, using his powers in creative ways to achieve his goals.
Kakashi could be a great main character as an ANBU commander. He has the skills, experience, and the mysterious allure that suits the role. He's known for his combat prowess and his ability to think on his feet, which are essential for an ANBU commander.
I really like 'Anbu Captain's Redemption'. In this fanfic, the Anbu captain has a dark past that he's trying to overcome. It's a great exploration of the character's psyche. The author does a wonderful job of integrating elements from the Naruto universe, like the use of jutsu and the relationships between different ninja clans. It also has some great fight scenes that keep you on the edge of your seat.
In most sakura anbu captain fanfics, Sakura is the main focus as she embarks on her Anbu journey. The Anbu captain, who is often a mysterious and powerful figure, is another main character. They are usually joined by other ninja comrades from their village who add more depth to the story with their different skills and personalities.
There's 'Sakura in Anbu: A New Beginning' which focuses on Sakura's journey as she takes on the challenges in the Anbu with the captain by her side. It has a lot of action and character development.
Well, the plot could involve Naruto having extraordinary powers that set him apart as a God - like figure. As an ANBU captain, he might lead his team on super - dangerous and top - secret missions. Maybe he uses his new - found God - like abilities to outwit and defeat powerful enemies that the normal shinobi can't handle. For example, he could have the power to instantly teleport to any location during a mission, which would give his team a huge advantage.
A fanfiction that stands out is 'Anbu Bond: Kakashi and Naruto'. This story focuses on the unique bond that forms between Kakashi and Naruto in the Anbu. It explores their past traumas and how they support each other to become better ninjas. It has a great plot that keeps you hooked from start to finish.
Perhaps a powerful shinobi from another village who has a special grudge against the Leaf's ANBU. He targets Kakashi and Naruto specifically because of their reputation within the ANBU. He has unique abilities that pose a great challenge to them, like the ability to nullify ninjutsu for short periods.
Perhaps a powerful and unknown shinobi from a far - off land. This shinobi has heard of Team 7's reputation and sees them as a threat to his plans of world domination. He uses his unique and mysterious jutsu to challenge Team 7 at every turn, and they have to figure out his motives and weaknesses to stop him.