One possible plot could be a battle over different ideologies. Ash might have grown to believe in a more compassionate way of treating Pokémon, while his father could have a more traditional, perhaps harsher view. This could lead to a physical or mental battle as Ash tries to prove his way is right.
Another reason might be differences in their goals. Ash is focused on befriending Pokémon and winning battles in a fair way. His father, on the other hand, could be more interested in power and prestige. This clash of values creates a rift between them, which is manifested in the form of a battle in the fanfiction.
He could be an ex - champion who had to give up his title for some noble reason. Now that he meets Ash, he wants to see his son reach the same heights.
In the fanfiction, Misty catches a Pokemon that has a special ability. Ash, being the competitive trainer he is, challenges her to a battle right away. The battle unfolds in a unique location, perhaps near a waterfall. Ash sends out his Charizard, and Misty uses her newly - caught Pokemon. The clash between fire and water - based attacks creates a spectacular scene.
I'm not entirely sure specifically what 'ash battles groundon fanfiction' is about without more context. It could potentially be a fan - made story where a character named Ash is involved in battles in a place called Groundon. Maybe it features Ash's adventures, his strategies in the battles, and how he overcomes various challenges in this fan - created scenario.
In 'ash battles groundon fanfiction', Ash is almost surely a main character given his name is in the title. Regarding Groundon, if it's a Pokémon - related fanfiction, Groundon is a powerful Pokémon. So it could be a main character in the sense of being an important entity in the battles. Additionally, there might be other trainers or Pokémon that Ash teams up with or battles against, which could potentially be considered main characters as well, depending on how significant their roles are in the overall story.
Well, one possible plot could be that Ash's father turns out to be a powerful Pokemon trainer who has been on a secret mission all this time. When they meet, his father shares some unique Pokemon training techniques with Ash.
One potential father figure for Ash in fanfiction could be Professor Oak. He has been like a mentor and a guiding figure in Ash's life. He has given Ash his first Pokémon and has always been there to offer advice, which could easily be developed into a father - like relationship in fanfiction.
In many Pokemon fanfictions, Ash's father is often left as a mystery figure. Some fanfictions might create an elaborate backstory for him, perhaps making him a powerful Pokemon trainer in a far - off region. He could be someone who had to leave Ash and his mother for some noble or dangerous quest related to Pokemon.
Ash might become more confident. Knowing he's the son of Sir Aaron could give him a boost in self - esteem. He could also become more mature as he tries to live up to his father's reputation.