In certain fanfictions, Ash might die from an incurable disease that he contracts while exploring a new and mysterious region in the Pokémon world. His Pokémon then have to deal with his loss and some might go on a journey to find a way to bring him back. For example, Pikachu could be determined to find a mythical Pokémon that has the power to revive the dead.
One good 'ash dies' fanfic could be 'The End of Ash's Journey'. It might explore how his friends react to his death and the impact on the Pokémon world. Another could be 'Ash's Final Battle and Demise' which could focus on a really epic and tragic final battle that leads to his death.
In fanfiction, if Ash were to die in Pokemon XYZ, it would be a huge shock to the Pokemon world. His friends like Pikachu would be devastated. Maybe Team Rocket would even feel a strange sense of loss. It could lead to a whole new storyline where his friends try to avenge his death or carry on his legacy of becoming a Pokemon Master.
There could be. Fanfiction is a very creative and diverse medium. Writers can take the Pokemon XY setting and create all kinds of scenarios, including ones where Ash meets an untimely end. But it might not be a common type of fanfiction because Ash is such an iconic and beloved character. His death would be a very drastic departure from the normal upbeat and adventure - filled Pokemon stories.
Ash would be extremely heartbroken. He might cry a lot and be in a state of shock at first. Then he would probably feel angry at the situation that led to Gary's death, whether it was a villain or just a dangerous accident. Ash would also feel a strong sense of responsibility, as if he has to carry on Gary's unfulfilled dreams.
One popular 'Ash Dies' Diancie fanfiction might be 'The Last Adventure of Ash and Diancie'. In this story, Ash's sacrifice could be tied to protecting Diancie's special powers from an evil force. Another could be 'Ash's Farewell in the Diancie Realm' where his death has a profound impact on the Diancie and the entire Pokémon world it inhabits. There could also be a fanfiction where Ash's death is a selfless act to save Diancie from a natural disaster in the Pokémon universe.
In a world filled with Pokémon battles and unwavering friendships, Ash stands as Serena's protector. One fateful day, a powerful and malevolent Pokémon appears, threatening Serena's life. Ash, without hesitation, throws himself in front of the attack. His body crumples to the ground as Serena screams in horror. She holds his lifeless form, tears streaming down her face. The Pokémon world mourns the loss of a great trainer, but Serena will always remember Ash as her hero.
There could be fanfics where Ash's death is part of a grander, darker story arc in the Pokemon world. Maybe he's killed as part of a conspiracy by an evil organization that wants to disrupt the balance of the Pokemon - human relationship. Such a complex and unique take on his death might attract readers and become popular.
One possible fanfic could be where Ash sacrifices himself to save Pikachu from a powerful and evil Pokemon. In this scenario, his friends are left to carry on his legacy and Pikachu becomes a symbol of Ash's selfless act.