A plot could revolve around Naruto being mistaken for a new Xiaolin Dragon. He then has to prove himself in the Xiaolin Showdown challenges while also trying to find a way back to his own world. Along the way, he makes new friends among the Xiaolin crew and discovers new aspects of his own powers as he adapts to the different challenges presented in the Xiaolin Showdown universe.
One idea could be a vampire infiltrating the Xiaolin temple to steal a powerful Shen Gong Wu for his own dark purposes. Maybe he plans to use it to gain control over other vampires or to create an army of the undead. Another plot could involve a Xiaolin monk being turned into a vampire and having to struggle between his newfound vampiric nature and his duties as a protector of the Shen Gong Wu. A third idea is that a vampire lord from the past awakens and challenges the Xiaolin monks to a showdown, with the fate of the world at stake.
Another idea is a story set in an alternate universe where Naruto is a Xiaolin Dragon. He could bring his ninja training and chakra abilities into the Xiaolin world. This would change the dynamics of how the Xiaolin Dragons usually operate as Naruto might have different strategies and a more aggressive fighting style compared to them.
One idea could be the discovery of a new power within the Dragon of Nature. Maybe it can communicate with all living things in a more profound way, leading to a new type of Xiaolin Showdown where the power to influence nature on a large scale is at stake. Another plot could involve a villain trying to corrupt the Dragon of Nature, and the Xiaolin monks have to go on a quest to purify it.
In a fanfiction, there could be a story about a tournament specifically for Mala Mala Jong within the Xiaolin Showdown universe. Characters from different parts of the world gather to compete. There could be intense rivalries, unexpected alliances, and of course, the discovery of new strategies and powers related to the game.
First, you need to do your research. Know the characters well from both Naruto and Xiaolin Showdown. Understand their personalities, powers, and backstories. This will help you write them in - character in your fanfiction.
A plot where there is an international Miraculous team-up. Heroes from different countries with their own Miraculous come together to face a global threat. They have different fighting styles and powers, and it's a challenge for them to work together against a common enemy in this showdown.
It could be about a new villain who tries to steal the power of the Dragon of Metal. The Xiaolin monks must then engage in a series of showdowns to protect it.
You could also set the fanfiction in a different time period or location. Imagine if the female OC travels back in time to an ancient Xiaolin Showdown. She could face challenges that are specific to that era, like different rules or more primitive opponents. This would require her to adapt and use her skills in new ways, making for an exciting story.
One common theme is the exploration of new powers for the OCs. Since in Xiaolin Showdown, powers are a big deal, OC fanfictions often create unique powers for their characters. For example, an OC might have the power to control time in a different way than the main characters in the show. Another theme is friendship. Just like in the original series, the OCs form bonds with the existing characters or with other OCs. They go through challenges together and their friendships are tested and strengthened. Also, the theme of self - discovery is quite prevalent. OCs in these fanfictions usually start with some unknown aspects about themselves, like not knowing the full extent of their powers or their true origins, and they go on a journey to figure these things out.
One idea could be a crossover with another popular sci - fi show. For example, the bionic heroes from Lab Rats team up with characters from a time - traveling show to stop an evil force that's using time - travel to change history and make bionics illegal. This would create a lot of interesting dynamics as they try to figure out how to work together.