The league officials and judges are also common characters. They are responsible for making sure the league battles are fair. Sometimes, in fanfiction, they might have a bigger role, like uncovering a cheating plot or having a special connection to a powerful Pokemon that could influence the outcome of the league.
Ash is obviously a very common character as the title includes his name. Pikachu, his trusty partner, is also likely to be there. His friends like Brock and Misty often appear as well. They might support Ash during his league journey or have their own sub - plots related to the league.
Gary Oak is a character that frequently shows up in such fanfiction. He could be a rival to Ash in the league, constantly trying to outdo him. Other trainers that Ash has met throughout his adventures in the official Pokemon series may also make an appearance, like May or Dawn. They could either be competing against Ash or cheering him on from the sidelines.
Ash is of course a very common character as he is the central figure. Pikachu is also often included as it is Ash's most well - known Pokémon. Other characters like Misty and Brock might also make appearances as they are Ash's friends and travel companions in the original Pokémon series.
Obviously, Ash is a common character. His friends like Brock and Misty might also make appearances. They could offer their own skills and knowledge to help Ash in his ranger adventures.
Some fanfictions might also include new characters that Ash meets on his return journey. These could be trainers with unique Pokemon or mysterious characters who have a connection to the events that led to Ash's return. For example, a young trainer who idolizes Ash and wants to learn from him, or a character who has information about a powerful Pokemon that Ash is interested in.
Obviously, Ash is a central character. Pikachu is also often there, as it's Ash's main Pokemon. Misty and Brock might be in the fanfiction too, trying to figure out what has happened to Ash and how to stop his evil ways. Sometimes, Gary Oak could be involved, either as an antagonist to Ash's new evil self or as someone trying to help bring him back to the good side.
Perhaps he defeats some of the Elite Four members who are participating in the league. They are known for their strength, so it would be a huge accomplishment. And of course, any recurring rivals from his past adventures like Trip or Paul.
Gary could be a common character in such fanfiction. Since he's Ash's long - time rival, it makes sense for him to show up at the Battle Tree. He might be there to test his skills against Ash or to prove himself as a better trainer.
Professor Kukui is another common character. He serves as a guide and mentor to Ash in the Alola region. He might provide Ash with new Pokémon knowledge, especially about the unique Alola Pokémon species. And of course, there are the various Pokémon trainers that Ash meets and battles in the Alola region. These trainers can range from novice trainers just starting out to more experienced ones who pose a real challenge to Ash.
In a fanfiction of Ash in the Unova League, it could focus on his relationships with his Pokemon during this journey. Maybe Pikachu has a special moment of growth, or he catches a new and rare Pokemon that becomes crucial in his battles in the league.
Another common character could be the Gym Leaders of the Unova region. They might appear as mentors or as judges in some of the Unova League events in the fanfic. Their presence can add authenticity to the story as they are an important part of the Pokémon world in the Unova region.
There are also often appearances from various Gym Leaders. They can serve as either allies or rivals to Ash. For instance, a Gym Leader might challenge Ash to a battle to test his newfound power, or they could join forces with him to take on a greater evil that threatens the Pokemon world.