One idea could be that Chesnaught and Greninja are on a quest to save their forest home from a mysterious dark force. They start as rivals, each thinking their own way is best to protect the forest, but as they face challenges together, they learn to work as a team.
Perhaps they could be from different tribes in the Pokémon world and are brought together by a prophecy. They initially distrust each other due to the long - standing differences between their tribes. However, through a series of adventures, they discover that they have more in common than they thought and become friends.
Another idea is that Greninja gets injured while on a mission and Chesnaught finds him. Chesnaught decides to nurse Greninja back to health. During this time, they share their stories and dreams, and when Greninja is fully recovered, they decide to travel together and face the world side by side.
A possible plot could be a tournament. Chesnaught and Greninja both enter a high - stakes Pokémon tournament. They meet in the semi - finals and have an intense battle. But then they realize that there is a conspiracy behind the tournament, and they join forces to expose it.
A great fanfiction idea could be that Greninja has a hidden power that only Ash can unlock. As they travel together, they encounter a series of increasingly difficult battles. In one crucial battle, Ash's belief in Greninja is what finally unlocks this power, leading to an epic victory.
One idea could be that Greninja, being a ninja - like Pokémon, somehow gets transported to the Naruto universe. It could team up with Naruto and use its water - based attacks in combination with Naruto's Rasengan. Maybe Greninja's ability to blend into the shadows could be used in stealth missions in the Hidden Leaf Village.
The 'alola greninja returns fanfic' might focus on Greninja's journey back to Alola. It could start with Greninja feeling a pull towards Alola, perhaps due to some unfinished business or a connection it still has with the place. Once there, it could encounter various Pokemon and trainers. There might be a story arc about Greninja finding its place again in Alola, dealing with changes that have occurred since it was last there, and forging new relationships while also rekindling old ones.
One idea is that Greninja is framed for a crime it didn't commit. It then has to go on the run while trying to prove its innocence. Along the way, it teams up with other outcast Pokémon and together they uncover a conspiracy that goes far deeper than they ever expected.
In the Pokemon Alola Greninja Ultra Adventures fanfic, Greninja may be a sort of guide or protector. It could lead other Pokemon or trainers through dangerous areas in Alola. It might also be involved in teaching new battle techniques to the local Pokemon or trainers. Given its agility and strength, it would be a very important character in the story, perhaps even having a special connection to some ancient Alolan power or legend.
One great greninja x delphox fanfic is 'The Bond Beyond Types' on FanFiction.net. It delves deep into their unique relationship, exploring how their different natures and abilities complement each other in unexpected ways.
The contrast between greninja's sleek, ninja - like nature and delphox's more elegant and magical aura. Their combination in a fanfic can lead to really cool interactions and storylines.
One popular 'ash and greninja fanfic' might be those where they face an extremely powerful and rare Pokemon together. In these stories, Greninja's unique abilities combined with Ash's leadership and battle strategies create exciting adventures. For example, they could be on a quest to save a region from a mysterious dark force. Greninja's water - type attacks and its transformation capabilities play a crucial role in the battles, while Ash's bond with his Pokemon gives them an edge.
A good fanfic of their reunion should have a strong emotional connection. Show Ash's excitement and Greninja's loyalty. Also, a great plot like a new threat they must face together.