A plotline might involve Ash being betrayed by a new acquaintance he meets on his journey. This person could pretend to be his friend, gain his trust, and then use that trust to steal his Pokémon or important items. Or perhaps Ash is betrayed by a Pokémon he just caught. The Pokémon could have been planted by an enemy trainer to spy on Ash and then turn on him at a crucial moment.
There could be a plotline where Ash is betrayed by the Pokémon League. Maybe they frame him for cheating or some other false accusation because they see him as a threat to the established order. This would make Ash an outcast not only among his friends but also in the entire Pokémon community. He would then have to fight to clear his name while dealing with the emotional pain of the betrayal.
Maybe in the fanfiction, Ash is given a Chespin by a mysterious trainer. This Chespin has some special powers that Ash has to figure out how to unlock. As they train together, they form a deep bond and go on to compete in a big Pokémon tournament where Chespin's unique abilities give them an edge.
One possible plotline could be that Ash and Cynthia are betrayed by a powerful villain who they once trusted. This villain might have been secretly working against them all along, perhaps stealing their Pokémon or sabotaging their quests. For example, the villain could be a rival trainer who was jealous of their success.
One possible plotline could be that Ash's so - called friends start believing false rumors about him and turn against him. Maybe a powerful enemy spreads lies that Ash has been secretly working for a rival organization. Another could be that Ash discovers a hidden power within himself that others fear, leading to his betrayal by those who don't understand it.
One possible plotline could be that Percy discovers his so - called friends have been secretly working against him all along. Maybe they spread false rumors about him, which makes everyone in his world turn against him. He then has to go on a journey alone to clear his name.
One possible plotline could be that Ash discovers May has been secretly working with a rival trainer in order to gain an advantage in a big tournament. This would make Ash feel betrayed as he thought they were friends and training partners. Another could be that May betrays Ash for a rare Pokémon that Ash was also after, choosing the Pokémon over their friendship.
One possible plotline could be that Ash makes a new friend during his journey who seems really great at first. But this new friend starts to spread false rumors about Dawn, making Ash believe them and slowly distance himself from Dawn, which she feels as a betrayal. Another could be that Ash gets an amazing opportunity in a new region, but in order to take it, he has to leave Dawn behind without proper explanation, which Dawn sees as a betrayal.
Well, often in such a 'ash gets betrayed fanfiction', the story might start with a seemingly normal day for Ash. Then, out of the blue, someone he trusts deeply, like Pikachu or one of his human friends, does something that he perceives as a betrayal. This could be something as simple as not believing in him during a crucial battle or siding with an enemy for a reason that's not clear to Ash at first. It can create a lot of emotional turmoil for Ash and make for a very engaging read.
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.
One possible plotline could be that her so - called friends in the Pokemon journey turn against her for some reason, like jealousy over her Pokemon's strength. Maybe they try to steal her Pokemon or spread false rumors about her to isolate her.
One possible reason for Ash getting betrayed in the fanfiction could be misinformation. A villain might spread false rumors about Ash, making his friends believe he has done something wrong. His friends, without verifying the truth, turn against him. It's a sad situation where lack of communication and trust plays a big role.