Well, in some fanfictions, he might get it from a skilled ninja prosthetics maker. This maker could be someone who specializes in creating artificial limbs for ninjas who have lost their arms in battle.
It could have enhanced strength. Since Naruto is already quite strong, the fake arm might be designed in the fanfiction to multiply his physical power, allowing him to punch even harder or hold heavier objects.
Well, it could be that he got it as a gift from some super - advanced ninja technology group in the fanfiction world. Maybe they saw his need for an extra weapon or tool during battles and decided to equip him with a metal arm.
One special ability could be enhanced strength. The metal arm might be able to deliver much more powerful punches than his normal arm, allowing him to break through tough defenses more easily.
Naruto may become more cautious. With a prosthetic arm, he realizes his vulnerability more. He might start to think more strategically before jumping into battles. For example, in a fight, he won't just rely on his brute strength but use the unique features of his prosthetic arm to his advantage.
One common theme is resilience. Naruto having one arm is a major setback, but in these fanfictions, he always bounces back. For instance, he might struggle at first but then finds ways to be as strong as before.
There could be a plot where Naruto's friends are overly protective of him at first, but he has to convince them that he can still fight and be useful. Also, the story might focus on how Naruto's relationship with Sasuke changes. Sasuke might see Naruto in a new light and feel a new sense of respect for him because of how he copes with the loss of his arm.
Yes, there might be. The Harry Potter fandom is vast and diverse, and fans often come up with creative and unique concepts like this for their fanfictions. There could be a writer who decided to give Harry Potter a metal arm in their story for various reasons, perhaps as a result of a battle injury or some magical - mechanical experiment gone wrong.
Naruto would need to train harder to make up for the lack of an arm. He could develop new jutsus or modify existing ones. Maybe he would start using more wind - based attacks that can be controlled with just one arm and his chakra control. Also, his friends might help him by creating prosthetics or assisting him in battles.
One plot idea could be Naruto using his prosthetic arm as a symbol of his past battles and how he overcame his injury. It could have special abilities like being able to store chakra more efficiently, allowing him to perform new jutsu. Another idea is that the prosthetic arm is a gift from an unexpected ally, which then leads to a whole new set of adventures and relationships as Naruto tries to figure out the true purpose of the arm.