In this kind of fanfiction, it might depict Ash having unique powers or a special bond with Mewtwo. Maybe Ash grows up with a different perspective on Pokemon battles, influenced by Mewtwo's intelligence and strength.
The main characters would surely be Ash and Mewtwo. But there could also be other Pokemon that play important roles. For example, Pikachu might have a different relationship with Ash since Ash was raised by Mewtwo. And perhaps some of Mewtwo's clones could also be involved, adding more depth to the story.
In a Pokemon fanfiction with Ash and Mewtwo, it could start with Ash encountering Mewtwo in an unexpected place. Maybe in a hidden forest where Mewtwo is observing the wild Pokemon. Ash, being his curious self, tries to approach Mewtwo. Mewtwo, initially hostile, realizes Ash's pure intentions and they start an unlikely friendship. This could lead to many adventures where Ash and Mewtwo face various challenges together, like battling against a new, powerful and evil Pokemon organization.
I'm not sure specifically as there could be many different interpretations in fanfiction. It might involve Mewtwo taking on the role of raising Ash in some unique, perhaps alternate universe scenario. Maybe Mewtwo sees potential in Ash and decides to guide and protect him in ways not seen in the original Pokémon story.
One possible scenario in this fanfiction could be that Ash encounters Mewtwo in a new, uncharted region. Mewtwo, being intrigued by Ash's unwavering spirit, decides to test him. Ash passes the tests with the help of his Pikachu and other Pokemon. This leads to Mewtwo seeing Ash as a worthy trainer and allowing itself to be caught. It would be a great twist on the usual Pokemon-catching storylines.
The two central characters would be Ash and Mewtwo. In this fanfiction, Ash is in a rather unique situation of being raised by Mewtwo. Ash is a well - known Pokémon trainer in the Pokémon franchise, and Mewtwo is a very powerful and complex Pokémon. There could also be other Pokémon that play important roles, perhaps Pokémon that are friends or foes to Ash as he grows up under Mewtwo's care. But at the heart of it, it's Ash and Mewtwo's relationship that drives the story.
The relationship can develop through shared experiences. For example, if they get trapped in a strange dimension together. They'll have to rely on each other to find a way out. This mutual dependence can lead to a stronger bond.
Typically, they often focus on the contrast between Ash's warm - hearted nature and Mewtwo's more complex and often aloof personality. Their relationship is usually at the center, exploring how they come to understand and care for each other.
Mewtwo's character can be developed further by exploring its emotions more deeply. For example, showing its fear of being alone or its longing for a true family. Fanfiction can also focus on Mewtwo's moral struggles, like whether it should use its powers for revenge or for good.
Well, Ash is known for his adventurous and curious nature. In Mewtwo's body, that adventurous spirit might be redirected. Instead of running around exploring physically, he might use Mewtwo's psychic powers to explore the minds of other Pokemon or discover hidden places in the psychic realm. His personality would also become more complex as he'd have to deal with Mewtwo's memories and emotions. He'd still be the same Ash at heart, but there would be an added layer of depth and thoughtfulness, perhaps a bit of melancholy too as he'd understand Mewtwo's pain of being created for the wrong reasons. And his interactions with other Pokemon and humans would be different. He might seem more intimidating at first because of Mewtwo's appearance, but as soon as he started to communicate, his friendly and helpful Ash - like personality would show through.