Perhaps in the fanfiction, Madara's neglect leads him to explore ancient and forgotten jutsu. He could use these newly discovered powers to show the ninja world what they've been missing by ignoring him. This could involve him making a grand display of his strength to gain the respect he believes he deserves.
Sasuke could be a main character as well. Given his own experiences of being an outcast and having a thirst for power at times, he could relate to Madara in some ways. They might form an unexpected alliance or have a rivalry based on their shared experiences of feeling neglected or misunderstood in the ninja world.
Madara could also save Naruto by using his knowledge of the ninja world. Maybe he has some inside information about a plot against Naruto and he intervenes in time to stop it. He might have discovered a secret plan by an enemy group and takes action to keep Naruto out of harm's way. This could involve manipulating events behind the scenes or directly confronting the threat.
Some fanfictions might depict Naruto as having a deeper understanding of the chakra system than ever before. He could have found a way to disrupt Madara's connection to the chakra source, or maybe he was able to use his own chakra in a way that nullified Madara's powerful jutsus. Also, Naruto's experience from all his previous battles might have led him to anticipate Madara's moves and strategies, allowing him to stay one step ahead and ultimately defeat him.
Yes, there might be such a fanfiction out there. The Naruto fandom is vast and creative, and fans often come up with unique and unexpected family relationships in their fan - created stories.
Well, in some versions of fanfiction, Naruto might have unlocked a new and super - powerful form of his Sage Mode. This enhanced form could give him the strength and speed necessary to outmaneuver and overpower Madara. Maybe he also gets some unexpected help from allies, like a new jutsu from Kakashi that weakens Madara's defenses just long enough for Naruto to land the final blow.
Perhaps he's been influenced by someone who gives him bad advice. For example, if someone tells him that natural talent is enough and training is overrated. Also, he could be dealing with some personal problems, like a conflict within his family or among his friends that takes up all his time and mental energy, causing him to neglect training.
He might start to rely on his friends more. For example, Sasuke and Sakura could become his main source of emotional support. He would focus on training with them and sharing his feelings, which in turn helps him to grow stronger and more independent.
At first, it might be very rocky. Naruto would be suspicious of Madara given his reputation. But as time goes on, if Madara shows genuine care and teaches Naruto useful skills, Naruto could start to respect him. Eventually, they could develop a father - son - like bond.
Well, in such a fanfiction, it might start with Naruto being in a situation where he becomes Madara's pet. Maybe at first, Naruto is defiant but as time passes, he could start to understand Madara's motives in some strange way. Madara, on the other hand, might initially see Naruto as just a possession but gradually develop a sense of attachment. It could be a really strange and complex relationship that unfolds as the story progresses.