One popular theme is the relationship between the protagonist and Blue Oak. It could be a friendship that develops through their Pokemon adventures. Another theme might be the exploration of different Pokemon regions in the context of the fanfiction. And sometimes, there are themes related to the evolution of Pokemon in unique ways that are not in the original games.
Another is his interactions with other characters from the Pokemon world. For example, how he might team up with someone unexpected and learn from that experience. Gary could also have a story where he discovers a rare Pokemon species and tries to protect it. This would involve facing off against poachers or other threats.
One popular theme is the adventure of the trainers from the blue and red versions teaming up. They might face a new, powerful and mysterious pokemon that wasn't in the original games. Another theme could be about the friendship or rivalry between the characters from the two versions evolving in new and unexpected ways. For example, they could have a competition to see who can catch a certain number of a rare pokemon first.
It can expand on the lore by delving deeper into Blue Oak's character. Maybe it reveals his backstory, like his family life or how he got into Pokemon training. It can also introduce new Pokemon species or variants that are unique to the fanfiction world.
A more adventurous storyline could be that Ash and Daisy Oak get transported to a different dimension where the rules of Pokemon are different. They have to figure out how to survive and find their way back home while also learning about the new Pokemon species in that dimension.
One popular theme is adventure. Since Ash is known for his Pokémon - journey adventures, fanfictions often include him and Daisy Oak going on new adventures together, exploring new regions or facing new challenges.
One popular theme is the development of the relationship between the main characters. The story often focuses on how they overcome obstacles and grow closer. Another theme could be the exploration of the medieval setting, like the courtly life and social hierarchies. Also, themes related to self - discovery and personal growth within the context of the story are quite common.
Well, it might be that Blue Oak is a character who has a rivalry with the main protagonist in the Red Pokemon fanfic. They could compete in Pokemon battles, and Blue Oak's unique strategies and Pokemon team could be a central focus. For example, he might have a team of Pokemon with special abilities that are not commonly seen in the regular Pokemon games, which makes his battles really exciting to read about.
Some fanfictions might focus on the relationship between Leaf and her starter Pokemon. Maybe it shows the growth and bond between them as they face different challenges together. There could also be storylines where Leaf discovers a hidden mystery in the Pokemon world that is related to the legendaries.
Blue Oak might be a healer in the fanfic. With his knowledge of Pokemon, he could heal injured Red Pokemon. This role would bring a different aspect to the story as he could also form bonds with the Pokemon he heals, and maybe some of these healed Pokemon end up joining his team or helping him in other ways later in the story.
I haven't actually read this particular fanfic yet. But if it's about Pokemon Special and involves Oak, Green or Blue, and a bird Pokemon, it could be really interesting. It might explore unique storylines like the relationship between the characters and the bird Pokemon, or perhaps some new adventures in the Pokemon Special world.