It could strain their relationship further. Naruto using such a powerful form against Sasuke might make Sasuke see Naruto as more of a threat than a friend, adding to the animosity between them.
In the fanfic, Naruto using Four Tails against Sasuke can be a turning point in their relationship. If Sasuke was underestimating Naruto before, this display of power makes him see Naruto in a new light. It could either push Sasuke to become more obsessed with getting stronger to match Naruto or, in a more positive turn, make him understand that they are on a more equal footing. This could potentially lead to a re - evaluation of their relationship, whether it's towards a more competitive or a more reconciliatory path.
In the fanfic, one key moment could be when Sasuke provokes Naruto during a battle. Naruto, in his rage, taps into the power of Four Tails. The sudden increase in power startles Sasuke and changes the dynamics of the fight.
Well, it probably makes his attacks more powerful. He might be able to deliver stronger punches and kicks as the chakra boost would enhance his physical strength. Also, his speed could increase, allowing him to move faster in battle and dodge attacks more easily.
In the fanfic, if Naruto kills the Sound 4, it could make Sasuke more competitive. He might see Naruto as having achieved a level of ruthlessness that he himself desires. Or, Sasuke could be disappointed in Naruto for resorting to killing. Their relationship would be full of tension as Sasuke tries to figure out where he stands in relation to a Naruto who has killed, and Naruto might struggle with Sasuke's reaction to his actions.
It could strengthen their relationship. By Naruto jumping in front of Sasuke, it shows Sasuke that Naruto still cares deeply about him and is willing to put himself in harm's way for him. This might make Sasuke more open to rebuilding their friendship.
It can strengthen the NaruHina relationship. Since Naruto hates Sakura and Sasuke, he might turn more towards Hinata for emotional support. Hinata's presence becomes even more important to him. He realizes that Hinata is the one who truly cares about him, not like Sakura who is preoccupied with Sasuke.
It has a huge impact on the story's pacing. Before Sasuke leaves, there might have been a certain rhythm to the story with their interactions. But once he's gone, the story has to find a new tempo. There could be a slow - down as Naruto mourns the loss, and then a build - up as he starts his journey to find Sasuke. The story also might shift its focus. Instead of their combined adventures, it could become more about Naruto's solo journey of self - discovery and his attempts to bring Sasuke back. This can introduce new themes like perseverance, loneliness, and the true meaning of friendship.
It can create a lot of internal conflict. For example, Sasuke's depression might cause him to make rash decisions that drive the plot. He could isolate himself from Naruto and the rest of the group, which then leads to the others trying to reach out to him. This pursuit can form a major part of the fanfic's plot.
It would strain their relationship. Sasuke's jealousy could make him act cold towards Naruto. He might avoid Naruto or be short - tempered when they interact.
It could make Sasuke more protective of Naruto. Sasuke has always had a complex relationship with Naruto, and seeing him lose an arm would stir up some deep emotions. He might feel guilty, especially if he was somehow involved in the incident that cost Naruto his arm. This could lead to Sasuke staying closer to Naruto and being more open about his feelings.
In fanfiction, the 'hot sauce punch' might be a turning point. It could make Sasuke realize that Naruto still has that goofy side and it might soften his cold exterior. On the other hand, if Naruto uses it out of anger, it could deepen the rift between them. For example, if Sasuke has just made a decision that Naruto strongly opposes, the punch could be a physical manifestation of his frustration.