There could be unfinished business between them. They might have a shared goal that they haven't achieved yet. Greninja's return to Ash in the fanfiction could be to finally complete that goal, whether it's winning a particular Pokemon tournament or saving a certain place from destruction.
Some fanfictions explore the idea of the two Pokemon learning from each other. After the battle, whether it's a win, lose or draw, they might exchange some sort of knowledge or experience. Maybe Greninja learns how to be more aggressive from Charizard X, or Charizard X learns about agility from Greninja. There are also plotlines where the battle is a test of friendship or loyalty between the Pokemon and their trainers.
One popular Ash and Ash - Greninja fanfiction could be those that focus on their adventures in a new, unexplored region. In these stories, they might face unique and powerful Pokémon, strengthening their bond along the way.
Well, in Alola, the battle environment is different. Ash Greninja has to adapt to the new battle rules like Z - Moves. It may start by observing local battles and learning from them. It could also adapt to the more friendly and less intense battle atmosphere compared to other regions. This means it might have to change its battle strategy a bit, not always going all - out from the start. And it might interact with different types of Pokemon that are native to Alola, which could lead to new friendships or rivalries, further shaping its adaptation to the Alola environment.
One common theme is adventure. Since both are involved in the Pokémon world, they often embark on exciting journeys together in fanfictions. Another theme is friendship. Writers like to explore how they become friends and support each other.
One idea could be a story where Ash, Cynthia, and Diantha team up for a special Pokémon tournament. They each bring their unique skills and Pokémon teams. Ash's determination, Cynthia's strategic mind, and Diantha's grace would make for an interesting dynamic as they face tough opponents together.
In some fanfiction, their interaction can be more of a mentor - mentee relationship. Diantha could be teaching Ash about the more advanced aspects of Pokémon battles, like strategic planning and reading opponents' moves. Their conversations would be filled with Pokémon knowledge and advice.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Ash Cynthia Diantha' on their search bars and you'll likely find a bunch of relevant fanfictions.
One great fanfiction could be 'The Journey of Ash with Cynthia and Diantha'. It has an interesting plot where Ash travels with the two strong trainers, Cynthia and Diantha, and they face various challenges together. They encounter powerful Pokémon and unique terrains. Another good one is 'Ash's Encounter with Cynthia and Diantha's Worlds'. In this, Ash gets to experience the different training styles of Cynthia and Diantha, which is really fascinating as he learns new techniques and strategies from them.
The 'pokemon ash x diantha fanfic' can be a great exploration of their potential relationship. It could start from their first encounter, which might be full of surprises. Then, as the story progresses, we might see how they grow closer. Their different backgrounds, with Ash being a young trainer from Pallet Town and Diantha being a famous champion, create a lot of room for interesting storylines. For example, Ash could learn a lot from Diantha's more refined training methods, and Diantha could be inspired by Ash's unwavering enthusiasm.