There could also be a mentor - like figure, maybe an old wizard or witch who has some knowledge about the founders and their heirs. This character could guide the young heirs, helping them understand their powers and the responsibilities that come with being an heir. They might be a bit of a mystery themselves, with a past that is slowly revealed throughout the fanfiction.
In addition, there could be friends or classmates of the heirs. They could be normal students who get caught up in the events surrounding the heirs. They might provide support, comic relief, or even be the ones to initially notice the strange powers or behaviors of the heirs, thus starting the whole story's chain of events.
Often, the main characters would be the heirs themselves. There could be a character who is the heir of Gryffindor, perhaps a young student who has always shown great courage and a sense of justice. Another main character might be the heir of Slytherin, who at first seems a bit of an outcast because of the negative reputation of Slytherin but turns out to have a complex and important role.
One interesting plotline could be the discovery of hidden magical abilities passed down from the founders. For example, a character might find they can communicate with the Hogwarts castle in a way no one else can, like feeling its emotions or getting secret knowledge from it. This could lead to adventures where they use this newfound ability to solve mysteries or protect the school from dark forces.
Obviously, the four founders - Godric Gryffindor, Helga Hufflepuff, Rowena Ravenclaw and Salazar Slytherin are main characters as they are being reborn. They bring their unique personalities and magical abilities back to the story.
The apprentice is obviously one of the main characters. They are likely to be a young wizard or witch with great potential. Then there might be characters representing the different houses of Hogwarts, like a descendant of Gryffindor who is a mentor to the apprentice. There could also be a rival apprentice who has different ideas about the founders' magic.
Neville could be an heir. He has shown great courage and a strong connection to the Hogwarts grounds. Maybe he is an heir to some ancient magic related to the protection of Hogwarts itself.
The main characters would surely include Harry Potter. Since it's about him meeting the founders, he's central to the story. As for the founders, they are key too. Godric Gryffindor might be the most enthusiastic about meeting Harry, seeing in him the true spirit of Gryffindor. Helga Hufflepuff could be the nurturing one, teaching Harry about the importance of hard work and loyalty. Rowena Ravenclaw might offer him wisdom, and Salazar Slytherin could present a more complex relationship, as his views on blood purity might clash with Harry's, but still be an important part of the story as Harry tries to understand and reconcile different magical ideologies.
You'll usually find characters like Godric Gryffindor, Salazar Slytherin, Rowena Ravenclaw, and Helga Hufflepuff. They might be present in spirit or through memories stored in the staff. And then there are the modern - day students who stumble upon the secrets of the staff. They could be original characters created by the fanfiction writer or minor characters from the original books who are given more depth in these stories.
Neville Longbottom is another possible heir. He has a strong connection to Gryffindor through his family's long - standing association with the house. His growth from a shy and clumsy boy to a brave and powerful wizard could be part of a story where he is the heir of the founders. His ability to stand up to the Death Eaters in the final battle shows his hidden strength, which could be related to the founders' magic.
Helga Hufflepuff is often quite popular. She represents kindness and loyalty, and in fanfiction, she might be portrayed as the one who keeps the founders together during their disagreements. Her character can be explored more deeply, like her backstory and how she came to value hard work and fairness so much.
Sometimes, the magical creatures that were around during the Founders' time can be popular characters in these fanfictions. For example, a phoenix that was a companion to one of the Founders and played a significant role in a particular event. They bring a touch of magic and mystery to the story and can be really engaging for readers.
I think in addition to the founders, characters like the first students they admitted can be quite popular. For example, if there was a particularly talented or mysterious first - year student in the fanfiction. Also, any descendants of the founders that might be introduced in the story could draw a lot of attention. They often carry on the legacies and sometimes the secrets of their ancestor founders.