Other main characters could be members of the Potter family that we don't know much about in the original series. For example, distant relatives who have their own motives and agendas regarding the family. There might also be antagonists from other families who are fueling the feud, such as some of the old pure - blood families who see the Potters as a threat or an annoyance.
Obviously, Harry Potter himself is often at the center of it. His friends like Ron and Hermione might also be involved as they support him through the family drama.
Then there are the Weasley family members who are closely related to Harry through his friendship with Ron. They might get involved in the Potter family feud either to support Harry or because the feud starts to impact their own family's standing in the wizarding world. And of course, Dumbledore or other important figures from Hogwarts could also play a role in trying to mediate or manipulate the situation depending on how the fanfiction is written.
Obviously, Harry Potter himself is a main character. He is usually the one who discovers or is in search of the family grimoire. Hermione Granger is also often involved as she helps Harry decipher the complex spells and ancient writings in the grimoire. Ron Weasley may be there too, providing support and his unique brand of humor.
Luna Lovegood could be one of the main characters. Her unique perspective on family and friendship could add an interesting dimension to the fanfiction. Neville Longbottom might also be involved. He has his own family story, and his growth and relationship with others could be explored in the context of family bonds. Additionally, Sirius Black could be a major character as he was like a father figure to Harry in some ways.
Harry Potter himself is often involved. He might be the one to encounter the first signs of inflation, whether it's a magically inflating potion or an enchanted object. His friends, like Ron and Hermione, are also likely to be part of the story, helping him figure out what's going on.
Ron Weasley could also be a key figure. He might be Harry's loyal friend as always, standing by his side during all the changes that Harry is bringing about in the wizarding world as a god. And there could be new characters introduced as well, perhaps other gods or magical beings that interact with Harry in this new fanfiction realm.
In some cases, Albus Dumbledore could play an important role. His wisdom and power in the wizarding world would make him a key figure in any situation where the two different universes collide. He might be the one to first discover Alexstrasza's presence and figure out how to make use of her abilities in the fight against the dark forces in the Harry Potter world.
Obviously, Harry Potter himself is always a main character. He is the one most directly associated with the concept of death in the original series, what with his parents' death and his multiple near - death experiences.
Ron Weasley could be another main character. He might be initially skeptical about the piano's magic but then be amazed when he sees the extraordinary things it can do. Maybe he accidentally discovers a new function of the piano while fooling around with it in the Gryffindor common room.
Harry Potter himself could be one of the main characters in such fanfiction. Maybe he gets an automail limb after a particularly dangerous encounter with Voldemort. Hermione might also be involved, using her vast knowledge to help understand and improve the automail technology within the wizarding context.
Well, of course, Harry Potter himself is often the central figure. He's usually the one who discovers the amulet or is tasked with dealing with its powers or secrets. Hermione Granger also frequently appears, using her vast knowledge to help Harry understand the amulet.
Harry Potter himself is often involved. He might be the one to discover a mysterious egg or be tasked with protecting it. Hermione Granger could also be a main character, using her vast knowledge to figure out the nature of the eggs. Ron Weasley might be there too, providing some comical relief while also helping with the situation.