Who could be the main antagonist in 'harry has dangerous pets fanfic'?

Maybe Harry has a dragon as a pet, and he has to hide it from the wizarding authorities. He faces challenges in training it and keeping it safe from those who might want to use it for evil.

It could be a new dark wizard who is jealous of Harry Potter's fame and success. This dark wizard targets Harry's child, thinking that by causing trouble for the child, they can somehow diminish Harry's reputation in the wizarding world. He might try to frame the child for various dark magic incidents around Hogwarts.

It could be an archaeologist who has been corrupted by the power of an ancient artifact related to the mummy. This archaeologist wants to use the mummy's power for his own gain, like becoming immortal or ruling the world. He would be constantly trying to stop Harry from helping the mummy.

It could be a powerful dark wizard who has also gained some supervillain - like powers. This antagonist might be jealous of Harry's newfound superhero status and wants to destroy him.

If the fake background was part of a larger conspiracy, the main antagonist might be the mastermind behind it all. This could be a powerful dark wizard who wants to use Harry's false identity to gain access to certain magical artifacts or secrets. The antagonist would be constantly manipulating the situation to keep Harry in the dark about his true role in the scheme.

It could be a jealous wizard who sees the relationship between Harry and the Lamia as a threat to his own power. He might try to disrupt the harmony in the circus and drive the Lamia away.

The main antagonist could be a powerful necromancer who combines the dark arts of Skyrim with some elements of Voldemort - like magic. He could be raising an army of the undead and causing chaos across Skyrim, which Harry has to stop.

It could be a new dark wizard who has a vendetta against Harry. This wizard might use a spell to stop Harry from eating, thinking it will weaken him before a final showdown. He could be someone who was once a follower of Voldemort and now wants to take his place and prove himself by getting rid of Harry.

It could be a rogue wizard who has infiltrated SHIELD and is using their technology for dark magic purposes. This wizard might be jealous of Harry's new position and try to undermine him.

It could be a jealous wizard who feels that Harry and his sister are getting too much attention in the wizarding world. This wizard might try to undermine their achievements and even put them in danger.