Well, Harry Potter would most likely still be a main character. His journey of growth and how he adapts to the evolving world around him would be a central focus.
Hermione Granger would also probably be a main character. Her intelligence would be useful in understanding the changes in magic and she could be involved in researching the evolution. She might also use her knowledge to help her friends navigate through the new situations.
Neville Longbottom could be a central figure in some Harry Potter Rebels fanfiction. He has shown great courage and the ability to stand up against the dark forces. In fanfictions, he might lead a rebellion against some corrupt elements in the Ministry of Magic. His growth from a shy boy to a brave hero in the original series gives him great potential to be a main character in these rebellious stories. And Luna Lovegood could also be important, with her unique perspective and disregard for convention, she could inspire others to rebel in the fanfiction world.
Another possibility is a new character created specifically for this fanfiction. This character could be a scientist or a wizard from a different part of the world who has knowledge of both nanotechnology and magic, and they bring the concept of nanobots into the Harry Potter universe.
Obviously, Harry Potter and Marris are the main characters. Harry is the well - known boy wizard, and Marris is the character specific to this fanfiction. There may also be other characters from the original Harry Potter series like Hermione and Ron, who might play supporting roles in the fanfiction.
Obviously, the grandchildren of Harry Potter are main characters. They often have names that are related to the Potter family traditions. There could also be their friends at Hogwarts, who might be from different wizarding families or even Muggle - borns.
Most likely, Harry Potter would still be one of the main characters. Since it's in the Harry Potter universe, he's central to the story. He could be the one around whom the new bonds are formed or strengthened.
In addition to the ones mentioned, Dumbledore could be a main character in some fanfictions. He knew Flamel, so he could play an important role in stories about Flamel. Voldemort could also be a main character as he was after the Philosopher's Stone, and his actions could be intertwined with Flamel's story. There could also be original characters created by the fanfiction authors who interact with Flamel and the other known characters.
There could be new characters created specifically for this fanfiction that are central to the merging concept. For example, a character who has the ability to control the merged magic or someone who is the key to uniting different groups of wizards that were brought together in this fan - made story.
Ron Weasley might be another main character. His loyalty to his friends and his sometimes comical, yet brave nature could be important in a story centered around a boomslang. There could also be new characters introduced in the fanfiction that are specifically related to the boomslang, like a character who is an expert on boomslangs or has a special connection to them.
Often, the main characters are still Harry, Hermione, and Ron. But with the addition of the nanites, their personalities and abilities might change. For instance, Harry could use the nanites to better understand Voldemort's magic.
It's hard to say for sure without reading it, but it could be that Harry, Hermione, and Ron still play major roles. They might be interacting with the gods in some way, either seeking their help or being caught in the middle of a conflict involving the gods.