It might be Iron Man. Tony Stark is intrigued by new and powerful things. Naruto's chakra - based powers would be something he'd want to study. And Naruto could benefit from Stark's technology. They could form an unlikely but effective alliance, with Stark providing high - tech gadgets and Naruto using his ninja skills in combat.
I think it could be Captain America. Cap is always looking for good - hearted individuals to fight alongside. Naruto's determination and loyalty would appeal to him. Also, Naruto could learn a lot from Cap's leadership skills.
Well, Naruto's ninja skills would be quite unique in the Marvel Universe. His chakra control would allow him to perform feats that might seem like magic to the Marvel characters. He could run up walls and across water, which would give him an edge in combat and in getting around. The Sharingan, if he had it, would also be a powerful tool for predicting his opponents' moves, much like some of the precognitive abilities in the Marvel world.
Well, Naruto's chakra - based powers could be quite unique in the Marvel Universe. His ability to use ninjutsu like the Rasengan could be seen as a very specialized form of energy projection. Maybe it would be considered a mutant - like power, or something completely new that S.H.I.E.L.D. would be very interested in studying. He could also use his shadow clone jutsu to outnumber his opponents, which would be a great advantage in battles against Marvel villains.
In a Marvel fanfiction with an immortal Naruto, his ninjutsu skills would blend in an interesting way. For example, his ability to use nature chakra could be seen as a form of magic in the Marvel Universe. This would attract the attention of Doctor Strange. They could have an exchange of knowledge, Naruto sharing about chakra and Strange about magic.
Well, Naruto's godlike powers could be quite a game - changer in the Marvel Universe. His ability to use chakra and perform jutsus like the Rasengan or the Shadow Clone Jutsu would be very unique. For example, the Rasengan could be as powerful as some of the energy - based attacks in Marvel. His shadow clones could be used for various strategies, like confusing enemies or gathering information. And his nine - tailed fox form would be like having a super - powerful beast within him, comparable to some of the hulking creatures in Marvel.
Captain America would be a great ally. They both have a strong sense of duty and honor. Captain America could understand Master Chief's military - like mindset and they could work well together in combat situations.
Batman in a Marvel fanfic would be a very interesting addition. His detective skills are top - notch, which could rival characters like Daredevil. He might have a hard time adjusting to the more super - powered and otherworldly elements in the Marvel universe compared to Gotham. But his intelligence and resourcefulness would make him a valuable asset to any team, perhaps even working with the Avengers on a mission that requires his particular set of skills.
If Naruto was in the Marvel universe as an immortal, he might be friends with Spider - Man. They both have a sense of humor and a strong sense of justice. Naruto could teach Spider - Man some new combat moves using his ninja skills. He might also respect Captain America for his leadership and unwavering beliefs. Naruto's immortality could make him a sort of mentor figure to the younger heroes in Marvel.
They could also be recruited by S.H.I.E.L.D. Fury might see their potential and want to use them in missions. Naruto would be eager to prove himself and help, while Sasuke would be more cautious. Their presence would cause quite a stir among the existing Marvel heroes, some being curious and others a bit wary of these new - comers with such different powers.
Dark Naruto might be introduced as a threat in a Marvel fanfiction. His darker nature could lead him to target powerful artifacts in the Marvel Universe, thinking they could enhance his power. For example, he could go after the Infinity Stones. His combat skills and unorthodox powers would make him a formidable adversary for characters like the Avengers.
If Harry Potter was in the Marvel Universe, he'd probably end up at Xavier's School for Gifted Youngsters. Think about it, a school full of mutants with special powers, and here comes Harry with his wizardry. He'd either be a great asset or cause a bit of a stir. His magical abilities would be a new kind of power that the X - Men and other mutants might not be used to dealing with.