Perhaps in the 'black blade naruto fanfic', the black blade has a connection to an ancient and forgotten clan. Naruto, being the main character, then delves into the history of this clan, uncovers secrets, and uses the knowledge and power associated with the blade to protect the Hidden Leaf Village from a looming threat that only he with the black blade can face.
In some fanfics, the black blade could change Naruto's fighting style completely. Instead of relying solely on his shadow clones and Rasengan, he starts incorporating sword techniques with the black blade. This could lead to new alliances and rivalries as other characters in the Naruto world either admire or fear his newfound power with the blade.
One interesting plotline could be the origin of the black blade. Maybe it's a weapon created by an ancient shinobi clan with a special power. For example, it could be a blade that absorbs the chakra of those it cuts, making the wielder stronger.
A possible plotline is a gender - bent Naruto having to prove herself in a male - dominated ninja society. She could form an all - female ninja team and take on missions that are typically thought to be for male - only teams. This would show her strength and determination in a different light compared to the original Naruto story.
One interesting plotline could be about Naruto unlocking a new and extremely powerful form in the 'naruto fury fanfic'. This form might be a result of his intense fury and determination, allowing him to face off against enemies he couldn't before.
One interesting plotline could be Naruto coming back reanimated and having to face new enemies that his old friends can't handle alone. His reanimated state might give him unique powers or abilities that change the course of battles.
One interesting plotline could be the exploration of Onikage's backstory within the Naruto universe. Maybe he has a hidden connection to a powerful clan that was long forgotten.
One interesting plotline could be the exploration of the unique culture and history of the Mist Village within the fanfic. Maybe it delves into the training methods of Mist ninjas that are different from other villages.
One interesting plotline could be about Naruto exploring an alternate universe within the Samsara concept. Maybe he discovers new powers or meets different versions of his friends.
One possible plotline could be how the characters in Naruto deal with the sudden outbreak of a Black Death - like disease. Maybe Naruto himself tries to find a cure using his shadow clones to search far and wide.
One interesting plotline could be the origin story of the black moon. It might explore how it came to be and what significance it holds in the fanfic's universe.
One interesting plotline could be Naruto's discovery of new and powerful sealing techniques. He might use these to defeat enemies in unique ways, like sealing away their chakra sources. For example, he could develop a seal that can nullify the effects of a powerful jutsu by sealing the energy that fuels it.