Perhaps in the fanfic, a new and mysterious Pokémon arrives. This Pokémon is able to manipulate the thoughts of those around it. It makes Mewtwo believe that Ash is a threat to all Pokémon. So Mewtwo starts to act against Ash. Ash, on the other hand, is clueless as to why Mewtwo has suddenly turned on him. He has to dig deep into the secrets of this new Pokémon and find a way to reverse what it has done to Mewtwo.
It could be that Ash discovers some sort of secret about Harrison that he misinterprets. Instead of talking to Harrison about it, he takes actions that seem like a betrayal. For instance, Ash might tell others about this secret, thinking it's for the greater good, but it actually causes a lot of harm to Harrison.
In such a fanfic, perhaps Ash and Paul were on a journey together in the Pokémon world. They might be part of a team for a big tournament. Then, one of them could make a deal with a rival group behind the other's back for personal gain, like getting access to a rare Pokémon. This would be the betrayal.
Well, one plot could be that Ash and Mewtwo are in a post - battle situation where they start to understand each other on a deeper level. Ash's pure heart makes Mewtwo question its view of humans. And as they interact more, a bond forms that gradually turns into a romantic - like relationship. But they have to face challenges from both the Pokémon world and human world who might not accept their relationship.
One common theme is the exploration of trust. When Ash and Mewtwo's relationship is broken by the idea of betrayal, it makes the reader think about how fragile trust can be. Another theme could be redemption. If Mewtwo has been made to betray Ash against its will, the story might focus on how it tries to make amends.
One possible plotline could be that Ash is betrayed by his so - called friends in the Pokémon world. They might spread false rumors about him, making everyone turn against him. Meanwhile, Mewtwo, who has formed an unlikely bond with Ash, is also betrayed by the scientists who created it again. They try to recapture Mewtwo to use it for their evil experiments. Ash and Mewtwo then team up to fight against their betrayers and prove their worth.
A possible plot for an 'Ash into Mewtwo' fanfic is that the transformation is a result of a wish granted by a magical Pokémon. Ash, now in Mewtwo's body, decides to use this opportunity to understand Mewtwo better. He travels to the places Mewtwo has been, meets the Pokémon Mewtwo has interacted with, and tries to solve the mysteries surrounding Mewtwo's creation. Along the way, he also has to face the consequences of having such a powerful form, like being hunted by Team Rocket who want to use him for their evil plans.
One possible plot could be that Ash discovers a female Mewtwo in a hidden location. She's scared and alone, and Ash decides to help her. They form a bond and go on adventures together, facing various Pokémon trainers and challenges along the way.
In this kind of 'ash and riolu betrayed fanfic', it might be that Ash and Riolu are in a Pokémon tournament. They meet a new trainer who seems friendly and offers to team up with them. However, during the tournament, this so - called friend betrays them by using underhanded tactics. This could include things like secretly weakening Riolu before a battle or spreading false rumors about Ash to other trainers. As a result, Ash and Riolu not only lose the tournament but also feel deeply hurt and betrayed.
The plot could involve Ash hearing rumors about Mewtwo's location. He sets out on a journey to find it. Once he does, he tries to communicate with Mewtwo. Mewtwo initially resists but Ash's pure intentions start to sway it.
One possible plot could be that Ash gets exposed to some strange energy during an adventure. This energy starts to transform him gradually into Mewtwo. As he changes, he begins to experience Mewtwo's memories and powers. He might struggle with this new identity, trying to figure out how to control the immense psychic abilities. Meanwhile, his friends are both shocked and worried, not sure how to deal with this new Ash - Mewtwo hybrid.