Another possibility is a scenario where Voldemort decides to expand his reach into the non - magical world and Batman becomes aware of this threat. He would then enter Hogwarts undercover to learn about magic and form an alliance with the Order of the Phoenix. The contrast between Batman's brooding, non - magical detective nature and the magical world would make for an interesting story.
A 'Batman the Harry Potter crossover fanfiction' might involve Batman teaming up with Harry Potter. Batman could teach Harry some combat skills from the Muggle world, while Harry could introduce Batman to magic. They could join forces to fight a common enemy, like a dark wizard who is using Muggle technology to enhance his dark magic. It would be a clash of two very different worlds and sets of skills.
One possible plot could be that Batman finds himself in the wizarding world of Harry Potter. He could use his detective skills to solve some magical mysteries that even the wizards are having trouble with, like a series of unexplained disappearances in Hogwarts. Maybe he teams up with Harry Potter and his friends, and Batman teaches them some non - magical self - defense techniques in return for learning about magic from them.
The interaction between the two sets of characters could also be quite comical at times. Imagine Batman trying to ride a broomstick for the first time. He would be all serious and business - like, but it would be a completely new experience for him. And the Hogwarts students would be in awe of Batman's cool gadgets and his Batmobile. Some of the minor characters in the Harry Potter world, like Neville, could gain confidence from seeing Batman's determination. And Batman could learn about the importance of friendship and loyalty from the tight - knit group at Hogwarts.
One possible plot could be that Voldemort's dark magic starts to seep into Gotham City. Batman, being the detective he is, starts to notice strange and magical happenings. Meanwhile, Harry Potter, Ron and Hermione get transported to Gotham through a magical accident. They team up with Batman to stop Voldemort's influence from spreading further. Harry uses his magic skills and Batman uses his gadgets and combat skills to take on the Death Eaters and Gotham's villains who have been corrupted by the dark magic.
The Joker could be an unexpected but exciting addition to this crossover. Imagine the chaos he could cause in the wizarding world. His madness and unpredictability would be a huge challenge for the wizards and witches. And Batman would have to find a way to stop him in a world full of magic, which he is not used to. Also, Snape's complex personality could add more depth to the story when interacting with Batman.
The characters' interaction could be really interesting. Harry Potter is used to dealing with threats using magic, but Batman uses his wits and physical strength. When they first meet, there might be some tension as they don't understand each other's worlds. But as they face a common enemy, they start to work together. Harry could show Batman how to use a broomstick, and Batman could teach Harry some hand - to - hand combat moves. Hermione would probably be trying to find a scientific explanation for Batman's abilities, while Ron is just happy to be part of this crazy adventure.
How about Gollum from Lord of the Rings? It seems really odd at first, but think about it. Gollum's sneaky nature and knowledge of dark places could be useful in Arkham Asylum. Batman could try to control Gollum's greed and use his skills to navigate the more dangerous parts of the asylum. And Gollum might be fascinated by Batman's shiny gadgets. It would be a very strange and interesting dynamic.
One idea could be that the Winchester brothers from Supernatural are investigating a series of strange murders in Gotham City. They cross paths with Batman who initially is suspicious of them. Eventually, they realize that a demon is behind the killings and they team up. Batman provides his detective skills and combat abilities while the Winchesters use their knowledge of the supernatural to defeat the demon.
Another one worth checking out is 'The Caped Crusader in RWBY'. It delves deep into how Batman's code of ethics might change or stay the same in the RWBY universe. It also has some great fight scenes where Batman uses his martial arts skills against Grimm, all while trying to understand the complex politics of Remnant.