Well, it's a really strange concept. Harry Potter and Spider - Man are from two completely different fictional universes. Harry Potter is about magic in a wizarding world, while Spider - Man is a superhero in a more modern, urban setting. But in the world of fanfiction, anything can happen. It could be an interesting mash - up if done right, with maybe Harry using his magic in Spider - Man's New York or something like that.
I'm not sure if there is such specific fanfiction. Fanfiction can cover a vast range of themes and ideas, but this particular combination of two very different fictional universes and a rather unexpected scenario might be a bit rare. It's possible that some creative fans out there have written something like this, but it would take some searching through fanfiction websites to find out.
Yes, there might be. The 'Harry Potter' and 'One Piece' (where Marineford is from) fanfic communities are quite large and creative. There could be a crossover where Harry Potter somehow saves Ace at Marineford. You can check fanfic platforms like Archive of Our Own or FanFiction.net to see if such a story exists.
In some fanfictions, Harry might use his magic skills. For example, he could use spells to protect Naruto from a powerful enemy. Maybe he casts a shield charm to block an attack that Naruto couldn't avoid on his own.
Well, in this fanfiction, it could be that Spiderman uses his agility and web - slinging skills to outmaneuver the enemy. Maybe he creates a huge web shield to protect the Avengers from a powerful blast. His spider - sense could also alert him to hidden dangers that the Avengers might not notice, allowing him to save them at the crucial moment.
Well, in such a fanfiction, it could start with a crossover event. Perhaps the multiverse theory is at play. Harry Potter, while on a magical adventure, stumbles upon a portal that leads him to Spiderman's New York. Spiderman, being the hero he is, tries to help Harry who is out of his element. As they work together to solve a problem that affects both their worlds, they develop an unexpected bond that culminates in a kiss. It would be a story full of contrasts, with magic and superpowers colliding, and two very different cultures coming together in an unlikely romance.
There are some fanfictions that focus on the relationships between the characters. Imagine a story where Hermione is a huge fan of Spiderman and she tries to figure out the science behind his powers using magic. Or a story where Peter Parker attends Hogwarts as an exchange student. He has to hide his identity as Spiderman while also learning magic, and he forms a close friendship with Ron and Harry. This kind of story often explores how different the two universes are in terms of technology and magic, and how the characters adapt to each other's worlds.
It could be some dark wizards who want to use the centaur's parts for potions. They might be following some ancient, dark magic recipe that requires centaur hair or hooves. So they hunt down the centaur, but Harry gets in their way.
In this fanfiction, perhaps the centaur is in a situation where it's about to be sacrificed in some dark ritual. Harry discovers this and races against time to stop it. He calls upon his friends Hermione and Ron for help. Hermione uses her vast knowledge of magic to figure out how to break the dark magic circle, while Ron provides some much - needed comic relief during the tense situation. Harry, of course, is the one who ultimately uses his powerful Patronus charm to dispel the dark forces and save the centaur.