Who could be the main villain in an 'aquaman harry potter crossover slash fanfiction'?

One possible plot could be that Aquaman discovers a magical portal in the depths of the ocean that leads to the wizarding world of Harry Potter. He then teams up with Harry to fight a new threat that is endangering both the underwater kingdom and Hogwarts. Maybe it's a dark magic - using sea creature that has gone berserk.

It could be a Death Eater who has somehow made a pact with a powerful force from Scorpian's world. This villain would be extremely dangerous as they'd combine the dark magic of the Harry Potter universe with the unknown and potentially deadly powers from Scorpian's realm.

One possible plot could be that Aquaman somehow finds himself in the wizarding world of Harry Potter. Maybe a magical spell gone wrong transports him there. He could use his unique underwater abilities to help the Hogwarts students in a task related to the Black Lake, like retrieving a powerful magical artifact that has sunk to the bottom.

Obviously, Kylo Ren would be one of the main characters. On the Harry Potter side, Harry Potter himself could be a main character. Their different views on power and good vs. evil could create a lot of interesting interactions. They could be at odds at first but then gradually come to understand each other.

Another option could be a new character created specifically for this crossover. This character could be a wizard who has studied the ninja arts and has become corrupted by power. He could start by causing chaos in the wizarding world, using his magic to mimic some of the more dangerous ninja techniques. Then, he could set his sights on the ninja world, seeing it as another source of power to be conquered. Fem Naruto and Harry Potter would have to put aside their differences and work together to stop him.

Voldemort could still be the main villain in a different way. Suppose he discovers Tonks' unique connection to Harry and tries to use her as a weapon against him. He could manipulate her mind or put her in dangerous situations to force Harry to make sacrifices or bad decisions.

Well, in a Harry Potter and Aquaman crossover fanfiction, we might see Aquaman's Atlantean magic interacting with Hogwarts' magic. For instance, the Sorting Hat might have a hard time sorting an Atlantean student brought by Aquaman. Also, Harry and his friends could go on an adventure to Atlantis with Aquaman as their guide, exploring the underwater world full of strange creatures and ancient magic.

A powerful dementor - like being that has been corrupted by Asgardian dark magic. This entity could be draining the life force of both wizards and Asgardians. It would be up to Thor and Harry Potter to find a way to stop it, as it poses a threat to both of their worlds.

Lex Luthor from Supergirl's world could be the villain. He could somehow find a way to travel to the wizarding world and team up with some dark wizards. He wants to use magic to enhance his power and take over both worlds. Supergirl and Harry Potter would have to stop his evil plans.

Well, it could be about Harry Potter using some Naruto - style jutsu in Hogwarts. Maybe he could learn how to do a shadow clone jutsu to help him with his studies and his adventures against Voldemort. And Naruto, if he were in the Harry Potter world, might be sorted into Gryffindor for his brave nature.