Dumbledore could be an unexpected ally. He might see this as an opportunity for Harry to stand up for himself and gain some closure on his difficult childhood. Also, some of the Hogwarts professors, like McGonagall, could be on Harry's side. They have always cared for Harry's well - being and would not tolerate the Dursleys' abuse. And there could be some new magical characters introduced specifically to help Harry in his legal battle, like a wizard lawyer who has a soft spot for underdog cases.
Luna Lovegood could be an ally. Her unique perspective might offer some creative solutions in building Harry's case. The Order of the Phoenix members would also be likely to support Harry. They are against the Dark Arts and any form of abuse. So, they would see the Dursleys' treatment of Harry as unacceptable. Some members might use their magical skills to gather evidence or protect Harry during the lawsuit process.
Perhaps Harry sues the Dursleys for false imprisonment. He realizes that all those years of being confined to his room or the cupboard were illegal. He enlists the help of Hermione, who is well - read in both wizarding and Muggle laws. They present a strong case against the Dursleys. As a result, the Dursleys face public humiliation in their neighborhood, and Harry finally gets the justice he deserves, while also starting to heal from the trauma of his childhood.
Some potential new allies could be the house - elves. They might see Harry's plight and decide to help him, using their unique magic and knowledge of Hogwarts' secrets. Another could be the centaurs in the Forbidden Forest. They are very wise and may take Harry under their wing.
His Hogwarts friends could be his allies. Ron and Hermione might come up with a clever plan to get Harry out. They could use the Weasley's magic - enhanced car to fly to Privet Drive and then create a diversion while Harry sneaks out. Another ally could be Hagrid. He has a soft spot for Harry and might show up with a large magical creature, like a friendly hippogriff, that Harry can ride away on.
Hermione would be a very likely ally. She's smart and resourceful, and could help Harry figure out the best ways to use magic against the Chitauri. Ron might also be there, with his loyalty and fighting skills. Additionally, some of the more experienced wizards or witches from Hogwarts could potentially join in to help Harry.
Hedwig could be a potential ally. She could carry messages to Harry's friends at Hogwarts, alerting them of his situation. Even though she is just an owl, she has shown loyalty and intelligence in the original series.
Hermione would most likely be one of his top allies. She's smart and well - read in wizarding law, so she could help Harry build his case. Ron would also be there for moral support and to offer his own unique perspective on things.
Ron and Hermione are almost surely his allies. They've always been by his side through thick and thin. Hermione's vast knowledge of magic and Ron's loyalty and courage would be invaluable in a mission to destroy the Ministry.
Hermione Granger could also be a rescuer. She was always intelligent and resourceful. In a fanfiction, she might figure out that Harry was in danger at the Dursleys' through some research or a hunch. Then she could use her knowledge of magic to break into the Dursleys' house and get Harry out. She would be brave enough to take on such a task to save her friend.
For Harry, his friends like Ron and Hermione are likely to be his allies. They've always been by his side through thick and thin in the original series, so it's natural for them to support Harry in a confrontation with Dumbledore. Neville could also be an ally, given his growth and courage shown in the books.
Harry Potter is a must - be main character. Among the goblins, there could be a young and adventurous goblin who is eager to prove himself. He teams up with Harry and they become good friends. Additionally, an old and experienced goblin elder who has a lot of knowledge about the history of the goblins and their relation to the wizarding world would also be a main character. He could guide Harry and the young goblin in their alliance.