Another concept is 'what - if' scenarios. What if the hero had made a different choice? What if the villain had a change of heart? These 'one shot ideas' allow for a lot of creativity as the author can take the story in a completely different direction while still using the existing characters and settings.
One interesting concept could be unique character interpretations. In 'one shot ideas fanfic', writers might present a character in a completely different light than the original source, which can be really engaging.
Well, you could do a naruto one shot fanfiction about Naruto going on a solo mission in a completely unknown land. He has to rely on his wits and basic ninja skills without the use of his signature jutsus. This would show his growth as a ninja beyond just his powerful techniques. Another interesting concept is a fanfiction where Naruto time - travels back to the era of the Sage of Six Paths and has to learn from him directly. Also, a story about Naruto befriending a jinchuriki from another village and how they both share their experiences could be really engaging.
One plot idea could be that Naruto and Karin are on a mission together in a dangerous, uncharted territory. They get separated from their team and have to rely on each other to survive. Karin uses her sensing abilities to find food and water sources, while Naruto protects them from the various wild beasts they encounter. As they spend time together, they start to understand each other on a deeper level and a bond begins to form.
Another concept could be alternative power-ups for Saitama. For example, instead of just his regular training regime, a fanfiction could give him a new kind of power boost through some unique encounter or magic item. This would add a new twist to his already overpowered character.
One interesting concept is alternate universe stories. For example, what if Luffy didn't eat the Gum - Gum Fruit but a different Devil Fruit? Another concept could be character backstories that are expanded or changed. Maybe a fanfic delves deeper into Sanji's time at the Baratie and creates new relationships or events during that period. Also, there are fanfictions that explore different power - up scenarios for the characters, like if Zoro found a new type of sword with unique abilities.
A plot could involve a fanfiction where Spider Man is shot by a mind - controlled civilian. This leads to a situation where he has to figure out how to stop the villain controlling the civilians without hurting them, all while recovering from the shot wound. He might also have to face public distrust as they see him as vulnerable now.
One interesting Harry One Shot Fanfiction could be about Harry's secret adventures during a forgotten summer at Hogwarts. Maybe he discovers a hidden room with ancient magic.
One interesting concept is a crossover with other popular anime like Naruto. Imagine Luffy and Naruto teaming up, it would be a clash of two very different power systems and personalities. Another concept could be a crossover with a superhero universe. For example, Luffy meeting Superman. Their powers are so different, it would make for an exciting story.
One interesting concept could be exploring the backstories of the characters in more depth. For example, delving into Saitama's life before he became so powerful. Maybe he had some hidden dreams or fears that are not shown in the original work.
In some One Piece gamer fanfiction, there's the concept of 'cheat codes'. These could be things like a secret knowledge that allows a character to instantly learn a new Haki technique or unlock a hidden island full of treasures. Also, the idea of character customization is popular. So, a fanfic might explore how Luffy could customize his straw hat or add new abilities to it, like making it a shield or a weapon enhancer.