What could be the plot of a fanfiction where Ash catches Yveltal?

Well, the plot could be as simple as Ash coming across a wild Dragonite that is injured. He helps it recover, and during the process, a bond forms between them. Eventually, Dragonite decides to join Ash's team. It's a classic 'help and befriend' kind of plot.

Perhaps Mew and Mewtwo are in a fight against an evil force that threatens the Pokémon world. Ash arrives at the scene and manages to communicate with them. He offers his help and through their combined efforts, they defeat the evil. As a result, Mew and Mewtwo see Ash as a true hero and allow him to catch them, leading to a new chapter in Ash's Pokémon journey.

Ash could catch Latias in a place full of ancient ruins. Latias might be guarding some sort of Pokemon relic there. Ash shows respect for the place and Latias' role. This makes Latias interested in him. Eventually, Ash catches Latias and they go on to discover more about the relic's power together.

One possible plot could be that Ash hears rumors of Rayquaza's appearance in a far - off region. He sets out on a journey with his Pokémon friends. Along the way, he has to face various challenges and other trainers who also want to catch Rayquaza. Eventually, he uses his unique bond with his Pokémon and his strategic skills to outwit Rayquaza and catch it.

One possibility is that Ash stumbles upon Meltan in an unexpected place, like a hidden grove. He uses his Pokémon knowledge and skills to gain Meltan's trust and catches it. Maybe he uses Pikachu to show Meltan that they can be friends and partners. This could lead to new adventures as Ash trains Meltan and discovers its unique abilities.

In another plot, Riolu could be a Pokémon that has been abandoned by its previous trainer. Ash stumbles upon it while on his journey. At first, Riolu is very distrustful of humans, but Ash shows it kindness and patience. Through Ash's training methods and the bond he forms with his other Pokémon, Riolu slowly warms up to him and allows itself to be caught.

It could be that Ash is on a journey to complete a special Pokémon collection. He hears about a rare Houndoom in a far - off land. When he finally finds it, he has to overcome not only the Houndoom's natural wariness but also various obstacles in the environment, like a maze - like forest. With his determination and the help of his Pokémon friends, he manages to catch Houndoom.

In the fanfiction, perhaps Ash catches Dratini during a quest. He hears rumors about a rare Dratini in a certain area. He goes there and finds Dratini being chased by some other Pokemon. Ash steps in to protect it and earns Dratini's trust. The story could then focus on their adventures together, exploring new regions and facing tough opponents with Dratini by his side.

Well, in the fanfiction, perhaps Ash catches Meowth to try and reform it. He might see that Meowth is not really a bad Pokémon at heart, just following the wrong crowd in Team Rocket. So he takes it under his wing, and they start to develop an unlikely friendship which changes both of them for the better.

One possible plot could be that Ash is on his Pokémon journey and stumbles upon a Haunter in an old, spooky forest. The Haunter might initially be mischievous, playing tricks on Ash and his Pokémon. But as Ash shows kindness and understanding, the Haunter starts to warm up to him. Eventually, Ash manages to catch the Haunter through a series of exciting battles and challenges, adding a unique and somewhat spooky addition to his Pokémon team.