Who could be the main antagonist in 'Harry Potter Prince of Hell' fanfiction?

The main antagonist could be the Devil himself. He might see Harry as an intruder in his domain and try to keep him there forever. He could set up all kinds of traps and challenges for Harry to overcome.

Another potential antagonist could be a jealous rival within Slytherin. This character might be envious of the 'Prince of Slytherin's status and popularity and would stop at nothing to bring him down. This could lead to a lot of internal Slytherin house drama and power struggles in the fanfic.

In this fanfiction, perhaps the 'Prince of Hell' is an ancient evil that has been slumbering for ages. Harry, being the hero, stumbles upon some old prophecies or artifacts that lead him to this discovery. His friends may not believe him at first, but as strange events start to occur around Hogwarts, they realize that Harry might be onto something really big and dangerous. He then has to find a way to stop this 'Prince of Hell' from causing chaos in the wizarding world and the Muggle world alike.

Perhaps a long - lost relative of the Potter family who feels they were unjustly excluded from inheriting the manor. This relative could be jealous of Harry's status and the wealth associated with the manor. They might use dark magic to try and claim what they think is rightfully theirs, leading to a battle of magic and loyalty within the Potter family and among Harry's friends.

It could be Malfoy. He might make fun of Harry for wearing a dress and try to use it to humiliate him in front of the whole school, which would then lead to a conflict between them that goes beyond the usual rivalry.

Perhaps a new dark wizard or witch who has infiltrated the Ministry of Magic and made sure Harry was sent to Azkaban. This antagonist could be working towards a bigger plan to take over the wizarding world and sees Harry as a major threat even when he's locked up.

Maybe a dark wizard who has an interest in Harry's newfound inheritance. This antagonist could want to steal his powers or use him for their own evil purposes. They might see Harry as a key to unlocking some ancient and powerful magic that they've been seeking.

Perhaps a group of dark wizards who think that by disrupting time, they can bring back the dark ages of wizardry. They target the Timekeeper as the only one who can stop them. They use dark spells and curses to try and stop the Timekeeper from fixing the time - related problems they create.

It could be Voldemort. He might see Harry's new waterbending ability as a threat and try to find a way to counter it. Maybe he would seek out dark magic related to fire to oppose Harry's water powers.

It could be a dark wizard who has the power to control bats and uses them for evil purposes. He might be trying to take over Hogwarts using his bat minions.