One possible plot could be that a new power emerges in the wizarding world, a group that has different ideals from Dumbledore. They manage to convince Harry that Dumbledore's way of running Hogwarts and his overall influence is harmful. Harry, being young and impressionable at times, sides with this new group and provides evidence, real or not, that causes Dumbledore to be fired.
It could be that Harry is influenced by some dark magic or a powerful enemy who manipulates him into believing that Dumbledore is a threat. So Harry starts to dig up dirt on Dumbledore, real or fabricated, and manages to get him fired. For example, if there was some misinformation spread about Dumbledore misusing school funds for his own personal gain, Harry might believe it and push for his dismissal.
In such a fanfic, perhaps Harry discovers some long - hidden, damning secret about Dumbledore. Maybe it's related to Dumbledore's past actions with Grindelwald. Harry, being the honest and justice - seeking person he is, feels compelled to expose this secret, which then leads to Dumbledore being fired from his position at Hogwarts.
It could be Voldemort or his followers. They might see Dumbledore as a major obstacle in their path to power. So they could manipulate Harry, perhaps through some mind - control magic or by spreading false rumors, to get Dumbledore fired. By removing Dumbledore, they hope to gain more control over Hogwarts and the wizarding world in general.
Well, it could be that Harry discovers some major misdeeds by Fudge. Maybe Fudge has been covering up dark magic activities within the Ministry. Harry then finds evidence and presents it to the proper authorities, leading to Fudge's dismissal.
Dumbledore would probably first have a long conversation with Harry. He would want to understand Harry's concerns thoroughly. Then, he would talk to Snape privately. Dumbledore is very protective of Hogwarts and its students. If he found that Snape's actions were truly endangering the students or the school's harmony, he might consider some form of disciplinary action, but firing Snape might not be his first option. He would also weigh Snape's contributions to the Order of the Phoenix and the fight against Voldemort. He has a lot of faith in Snape, but he also respects Harry's instincts and would take his feelings into account.
There may be such extremely non - canon and inappropriate fanfiction out there in the vastness of the internet, but it goes against the original nature and values of the Harry Potter series. J.K. Rowling's world has certain boundaries and this concept is far from what was intended in the original story.
In a 'Harry Potter gets revenge on Dumbledore' fanfiction, Harry could find out that Dumbledore knew about certain threats to his life but didn't do enough to protect him. So, Harry decides to get revenge by undermining Dumbledore's influence at Hogwarts. He might start by convincing the other students that Dumbledore isn't as infallible as they thought. He could do this by revealing some of Dumbledore's past mistakes. Then, he could work on getting the school governors to question Dumbledore's leadership, gradually chipping away at his power and status within the wizarding community.
Well, perhaps Harry discovers some dark secret about Dumbledore that makes him feel he must escape. It could be that Dumbledore is being controlled by some dark magic and Harry realizes he's in danger around him.
One possible plot could be that Harry discovers some dark secret about Dumbledore's past actions and decides to oppose him. For example, if he finds out that Dumbledore had some sort of deal with the Dark Arts that he hid from everyone. This would make Harry feel betrayed and drive him to defy Dumbledore.
One possible plot could be that Harry discovers a powerful and ancient magic that Dumbledore has been trying to keep hidden. Harry's newfound knowledge and power make Dumbledore fear that he will disrupt the delicate balance in the wizarding world. So, Dumbledore starts to act nervously around Harry and tries to subtly keep him in check.
Yes, there might be. In the vast world of fanfiction, all sorts of creative and unexpected scenarios are explored. Some authors might come up with the idea of Dumbledore being afraid of Harry for various reasons. It could be due to Harry's newfound power that he doesn't fully understand, or perhaps a prophecy that takes an unexpected turn in the author's interpretation. Fanfic writers often like to play with the established characters' emotions and relationships in unique ways.
Hermione could be a great help. She is very intelligent and resourceful. She could help Harry find evidence against Snape. For instance, if Snape is suspected of cheating in grading, Hermione could use her knowledge of Hogwarts' grading system and records to dig up proof.