In this fanfiction, perhaps Harry decides to renovate Hogwarts. He could add new sections for different types of magic study, like a special wing for time - traveling magic research. Also, as the owner, he'd have to deal with the political aspects of the wizarding world trying to influence the school's curriculum.
The plot might revolve around Harry's struggle to maintain the balance between tradition and progress at Hogwarts. He is the owner now, so he has to respect the old ways that the founders set up, but also wants to bring in modern ideas. For example, he may introduce Muggle technology in a limited way to enhance the learning experience of students, all while fending off those who oppose such changes.
One possible plot could be that Harry discovers he has some ancient claim to Gringotts. He then has to deal with the goblin politics and power struggles within the bank. Maybe he tries to reform some of the old and unfair practices at Gringotts.
Obviously, Harry Potter himself. Then there would be his friends like Hermione and Ron. They could be his advisors or teachers at Hogwarts. Dumbledore might also make an appearance in the form of a memory or a portrait that gives Harry guidance. And of course, the students of Hogwarts would be important characters too.
Well, it could be about Harry facing an even greater threat than Voldemort. Maybe a new dark wizard emerges from the shadows and Harry has to use all his skills and the support of his friends to defend Hogwarts as its champion. He might have to go through a series of super - difficult challenges that test his magic, courage and loyalty to an extreme level.
One possible plot could be that Harry Potter, as the new owner of Hogwarts, decides to reform the school's curriculum. He might introduce new magic subjects that were previously overlooked, like ancient rune magic for practical applications.
Perhaps Harry is teaching Potions in the fanfiction. Since he had a bit of a rocky start with Potions in his student days, he could be a very understanding teacher. He might encourage students to experiment more, which is different from Snape's strict methods. He could also share stories about how important Potions were in his adventures, like when they made Polyjuice Potion. This would make the class more interesting and inspire students to take Potions more seriously.
Well, it could be about Harry's journey to fully embrace his role as a prince in Hogwarts. Maybe he discovers some long - lost royal heritage of the wizarding world that gives him new powers and responsibilities.
Well, perhaps the plot could involve Harry using his newfound powers to bring about major reforms in Hogwarts. He might control the curriculum to include more practical magic for real - world situations.
One possible plot could be that Harry travels back in time to become the founder. He uses his knowledge of future dark wizards to set up defenses in Hogwarts. For example, he could create a special chamber to hide something crucial, just like the Chamber of Secrets, but with a different purpose.
One possible plot could be that Harry, as the 'King of Hogwarts', uses his new - found status to reform the school's rules. He could make the houses work together more closely, perhaps by creating new inter - house competitions that focus on cooperation rather than competition. For example, a magical scavenger hunt where students from all houses must team up to find hidden magical artifacts around Hogwarts and its grounds.
It could be that there's a powerful enemy that has taken over Hogwarts and Harry, in a desperate attempt to stop this evil from spreading, resorts to destroying the school. He might think that rebuilding it later is better than allowing it to be used for evil purposes. For example, if Voldemort had found a way to permanently taint the magic of Hogwarts, Harry might see destruction as the only option.