One of the most popular has to be Giratina. Its other - worldly and somewhat menacing appearance can be made into humorous situations. For example, Giratina getting scared of a Caterpie that crawls on it in a fanfiction. Ho - Oh is also popular. Its association with legend and beauty can be turned on its head. Picture Ho - Oh losing a feather and chasing a little Rattata that stole it all over the place. And Dialga, with its time - controlling abilities, can be in some really funny time - loop situations in humor fanfiction, like repeating the same embarrassing moment over and over again.
Well, one interesting aspect is the way it can play with the over - the - top powers of legendary Pokemon. For example, making Articuno use its ice powers to create ice sculptures of other Pokemon in really goofy poses. Another aspect is the character interactions. Imagine Mewtwo trying to understand the simple - minded humor of a Pikachu in a fanfiction. It can also be interesting how the fanfiction might use the mysterious nature of legendary Pokemon to create comical misunderstandings, like Dialga accidentally messing up time and causing all the Pokemon to have their voices switched.
Articuno, Zapdos, and Moltres are quite common. Their elemental powers and the mystery surrounding them make for great fanfiction material. Ash might encounter them during his travels and have to either help them or face off against them in some way.
One of the Legendary Pokemon could be Giratina. Despite its somewhat dark and otherworldly nature, Giratina might be intrigued by Ash's light - heartedness and his ability to make friends with all kinds of Pokemon. Dialga and Palkia could also be part of the harem. Dialga, with its control over time, might see Ash as an important factor in the future of the Pokemon world. Palkia, in charge of space, could be interested in how Ash navigates different regions and spaces in his journey. And don't forget about Ho - Oh. Ho - Oh is a symbol of hope and might see Ash as a bringer of hope in the Pokemon world, thus joining his harem.
Arceus is quite popular. Given that it's considered the creator of the Pokemon universe in the official lore, it often has a significant role in fanfictions. Mewtwo is also very common. Its powerful psychic abilities and complex backstory make it a favorite for fanfic writers to explore. Another popular one is Lugia. With its majestic appearance and its connection to the sea, it's often a central figure in many stories.
Mewtwo is also very popular. Given its origin as a genetically - engineered Pokemon, a human could interact with it in many ways. Maybe a human scientist wants to study Mewtwo further, or a young trainer tries to befriend Mewtwo and help it come to terms with its existence and powers.
There are also fanfictions where Ash catches Rayquaza. This could be set during a time when the sky is in chaos due to some dark energy. Rayquaza is drawn to Ash because of his pure heart and determination. Ash, with his usual courage, teams up with his pokemon to assist Rayquaza in restoring balance. As a result, Rayquaza allows Ash to catch it.
The appeal lies in seeing Ash in new and exciting situations. With legendaries involved, his journey becomes more epic. It's like taking the underdog story of Ash in the anime and supercharging it.
In Ash-centered legendary Pokemon fanfiction, often Ash has extraordinary adventures. He might form unique bonds with legendary Pokemon that are not seen in the official storylines. For example, he could befriend a Mewtwo and together they face off against an evil organization trying to clone more powerful Pokemon. These fanfictions allow for a lot of creativity, expanding on Ash's character and his relationships in the Pokemon world.
Maybe a story about a human who accidentally stumbles into the hidden realm of Legendary Pokemon. There, they form a friendship with a Legendary that is an outcast among its kind. Together, they try to change the perception of the outcast Legendary in its own community while also finding a way for the human to return home.