Another idea is a time - travel fanfiction. Harry goes back in time and has to deal with Umbridge when she was a student. He tries to change her path so that she doesn't become the horrible person she is in his time. This could involve him befriending her and showing her the value of kindness and freedom.
In some versions, Snape uses his knowledge of the Dark Arts and Hogwarts' secrets. He might set up a situation where Umbridge is lured into a restricted area of the castle and gets into trouble with some magical creature or ancient magic, causing her to be removed from her position.
One possible reason could be that Snape still has an underlying sense of loyalty to Dumbledore. Since Dumbledore cares about Harry, Snape might step in to save him from Umbridge's cruelty. He doesn't want to see Hogwarts turned into a place of unjust persecution under Umbridge's regime, and Harry is a symbol of the resistance against that.
A good 'Harry Potter destroys Umbridge' fanfiction often has a strong plot. It should show Harry using his unique qualities, like his courage and loyalty to his friends. For example, he might stand up to Umbridge's unjust rules in a really clever way that shows his Gryffindor spirit.
In some fanfictions, the Weasley twins play a major role in exposing Umbridge. They use their pranks not just for fun but as a way to draw attention to her unfair rules and cruel treatment of students. For example, they might set up a series of magical traps around the school that, when triggered, expose some of Umbridge's secrets.
These fanfictions often explore the themes of justice and standing up to authority, which are important in the 'Harry Potter' universe. Readers enjoy seeing the characters they love take a stand against Umbridge's tyranny, so it makes these stories popular.
One possibility is that Umbridge, despite her cruel nature, sees some potential in Harry for her own gain. Maybe she tries to mold him into a perfect little wizard according to her strict and often wrong ideas. She could isolate Harry from his friends and force him to follow her rules blindly, which would create a lot of internal conflict for Harry as he tries to resist her brainwashing while living under her roof.
Obviously, Harry Potter is one of the main characters. He is the central figure in the fight against Umbridge, using his courage and leadership skills. Hermione Granger would also be a main character. Her intelligence and knowledge of magic are crucial in coming up with plans to oppose Umbridge.
A common theme is justice. Since Umbridge is such a hated character for her cruel and unjust ways, fanfictions often focus on Harry or other characters seeking justice for her victims. Another theme is the fight against oppression. Umbridge represents a form of oppression in Hogwarts, and the characters in the fanfictions usually rise up against her.
It might be. There are a lot of fans who like to see different takes on the relationships between characters in the Harry Potter universe. If the fanfiction is well - written and the idea of Harry having 'fun' with Umbridge is presented in an interesting way, it could attract a fair number of readers.