Naruto would likely be stronger in a direct combat situation. He has been through numerous battles, has a vast array of jutsu at his disposal, and his physical strength and speed are enhanced by his ninja training and the Nine - Tails. Shin Natsume, while having interesting spiritual powers, may not be as well - equipped for a full - on battle. But Shin's powers could be useful in a support role, like helping Naruto detect hidden enemies or sense danger from afar.
The plot might involve Naruto entering the Kyuubi's mental space in a new and more powerful way. He could bring with him some sort of 'light' or positive energy that is anathema to the Kyuubi. This positive energy could represent all the good things in Naruto's life, like his friends, his dreams, and his love for the village. The Kyuubi, being a creature of darkness and power, is scared by this pure and positive force. Or maybe Naruto discovers a hidden weakness of the Kyuubi through his own growth and understanding. He then exploits this weakness, causing the Kyuubi to be afraid of what Naruto could do to it.
In the fanfiction, Naruto could have been possessed by some dark force. This dark - Naruto then starts to act in a very unpredictable and scary way, like randomly attacking people with great force. He might also have a really creepy look in his eyes, which scares everyone around him. The villagers who once knew Naruto as a friendly ninja would be shocked and terrified.
Naruto could develop his strategic thinking skills. By scaring Zabuza, he realizes that he can use psychological warfare in addition to his regular combat skills. So he starts to study his opponents more closely to find their weaknesses.
It could be another powerful entity that is secretly manipulating the situation. Maybe there is a dark shinobi or a hidden organization that wants to see the Kyuubi and Naruto at odds. They could be the ones who set in motion the events that lead to Naruto scaring the Kyuubi. For example, they might have given Naruto a false power or false information that is causing the Kyuubi to be scared, all in an attempt to further their own evil plans. This entity would then be the main antagonist as they are the real source of the conflict.
His close friends like Sasuke and Sakura would likely be among the most affected. They know Naruto well and seeing him in a terrifying state would be very shocking for them. For Sasuke, who has a deep bond with Naruto, it would be especially hard to face a scary Naruto.
The Shining was a classic horror film directed by Stanley Kubrick and released in 1980. The movie was about a lonely hotel owner and his family staying in a seemingly comfortable but actually extremely scary room. As time passed, they began to find themselves trapped in a mysterious and terrifying world.
The film received high praise and reputation around the world and was considered a classic in the history of film. The horror atmosphere and the design of the thrilling scenes were widely imitated and used as a representative work in the history of movies.
One possible reason could be to protect Hinata. Maybe Sasuke has unknowingly made a move or decision that Naruto perceives as a threat to Hinata, so he scares Sasuke to make him back off.
Hinata might be initially worried. She doesn't want any conflict between Naruto and Sasuke because she cares about both of them. But at the same time, she could feel a bit flattered that Naruto is so protective of her.
I recommend the following novels to you, all of which are novels in which the protagonist controls ghosts to scare people: " Crazy, Interns Are Cheating ": The protagonist can see through and control the medicine to kill viruses. At the same time, he can also use hypnosis. 2. " Fei Chang Special Ability: BenGong is coming, please close your eyes ": The female lead can use powerful hypnotism.