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.
One possible plot development could be that after saving Naruto, Madara tries to mentor him. He sees Naruto's potential and wants to shape him into an even greater ninja, sharing his own knowledge and skills that have been honed over years.
One possible plot could be that Madara, seeing Naruto in a dangerous situation related to a love interest, decides to step in. Maybe Naruto's love is being threatened by an enemy who wants to use their relationship for some dark purpose. Madara, with his powerful abilities, fends off the enemy and in the process, Naruto realizes Madara has a more complex side than he thought. This could lead to a change in their relationship dynamic, perhaps even a friendship that forms the basis for some interesting interactions in the future of the fanfiction.
It can bring a new perspective to the fandom. Some fans who enjoy Yaoi might be really excited about this concept as it combines two popular characters in a different kind of relationship. It can also inspire more fanart and fan - made content related to this specific scenario.
It could be that Might Guy is under some sort of mind - control. So, without his normal self - control, he attacks Tenten, making it necessary for Naruto to save her.
Well, one possible plot twist could be that Madara's reason for saving Naruto is not entirely selfless. Maybe he has a hidden agenda related to some ancient prophecy in the Naruto universe. He might see Naruto as a key to achieving something greater for himself or his clan.
Maybe an old enemy of Madara who realizes that by targeting Naruto, he can get back at Madara. Since Madara has some sort of connection or interest in saving Naruto in this fanfiction, the enemy thinks that if he can harm Naruto, he can either draw Madara out or simply cause him pain. This enemy could be a powerful rogue ninja with a vendetta against Madara.
In some fanfictions, it could be through a strange and powerful jutsu transfer. Maybe Madara, on the verge of defeat, decides to transfer his Rinnegan power to Naruto for some unforeseen reason, like seeing a new path for the ninja world in Naruto.
Sasuke is often a popular character in these fanfictions. He might play a role in helping Naruto against Madara or have his own motives during their battle. Kakashi can also be a prominent figure, perhaps using his Sharingan in a crucial moment to assist Naruto. Another popular character could be Hashirama, as his connection to Madara is a key part of the original story and can be further explored in fanfiction.