Perhaps the story could be set in a region where Rockruff is considered a symbol of good luck. Ash hears about this and decides he wants to catch it not just for his team, but also to understand the local beliefs. Along the way, he meets different characters who either help or hinder his quest to catch Rockruff. There could be a lot of emotional moments as Ash tries to bond with Rockruff and convince it to join his team.
Well, often the best place to look for such a fanfiction is specialized Pokémon fanfiction communities. These are places where fans gather to share their works. Some might be on Reddit, in Pokémon - related subreddits. People might post links or even write the fanfiction directly there. You could also check out some Pokémon fan blogs, as they sometimes feature fan - made stories like 'Ash catches Rockruff'.
Maybe it starts with Ash on his journey and he stumbles upon a Salamence in a unique situation, like it's injured or lost. And he decides to catch it to help it and also add it to his team.
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.
One possible plot could be that Ash is on his journey and stumbles upon a lost and injured Sylveon. He decides to take care of it, and through their time together, they form a strong bond. Eventually, Sylveon decides to join Ash's team.