Well, aside from Percy himself, there could be a wise old owl as a mentor figure. The owl could teach Percy about the secrets of the wild, like which plants are safe to eat and which are poisonous. There might also be a wild horse that Percy befriends and rides. This horse could be his loyal companion during his adventures in the wild.
Obviously Percy himself. There could also be some of his friends from his normal life who come to visit him in the wild or maybe even join him, like Annabeth. And then there could be various wild animals that act as characters, like a wise old owl or a friendly deer.
Another potential character could be a dragon oracle. This oracle could have the ability to see Natsu's true nature and destiny. They could either help Natsu understand his powers and purpose or be a bit of a trickster, making Natsu's journey to discover himself even more difficult. And of course, the other members of Fairy Tail would be there to support or sometimes misunderstand Natsu as he deals with his dragon - born identity.
In the 'Percy born in the wild fanfiction', perhaps Percy is born in a wild, post - apocalyptic landscape. He has to fend for himself from a young age. There are scarce resources, and he has to fight off gangs of raiders. But he also discovers that there are remnants of ancient magic in this wild world, and his birth might be related to unlocking the secrets of this magic to restore the world to a better state.
There could be a female mentor who takes Ash under her wing because she sees potential in her as a girl in a male - dominated world. This mentor could teach her unique skills and ways of dealing with Pokémon. Another potential new character could be a rival who is also a girl and has a different view on how to compete in the Pokémon world compared to Ash. They could have some interesting battles and exchanges of ideas.
There could be new characters as well, like a devil mentor figure who teaches Percy about his devil heritage. This character could be ancient and have a lot of knowledge about the devil realm. Or there could be an angelic character who is initially an enemy but later realizes Percy is not fully evil and they end up forming an unlikely alliance.
Obviously Percy is the main character. There could also be other characters from the original series, like Annabeth. She might be worried about Percy's transformation and try to help him adjust. And maybe some of the gods would also be involved, either trying to control Percy or use his new powers for their own ends.
Obviously, Percy would be the main character. There could also be some characters from the original Percy - related universe who might make an appearance to help him adjust or just to check on him. And from the Forks side, characters like Bella or Edward (if it's in the Twilight - Forks setting) could potentially cross paths with Percy. Maybe they become friends or foes depending on how the story unfolds.
Maybe there is a social worker named Mrs. Johnson who is trying to help the homeless in the area. She tries to reach out to Percy, but he is initially hesitant because he has trust issues. These characters can all interact with Percy and shape his story while he lives on the streets.
Obviously, Percy would be the main character. As he is the one born a god in this fanfiction.
In addition to Percy, there could be a healer or a magic - user who tries to find a way to cure his blindness. This character would be important as they drive part of the plot. And of course, Percy's closest friends, who are with him through thick and thin, would also be main characters. They share his joys and sorrows and are there to protect him when needed.