One idea could be creating an OC who is a devil hunter from a different country with unique fighting techniques. For example, an OC from a martial - arts - rich nation like Thailand, who uses Muay Thai moves along with devil - powered weapons. Another idea is an OC that is half - devil and half - human, struggling with their identity and trying to find their place in the world of Chainsaw Man. They could have powers that are a blend of both devil and human capabilities, making their story full of internal conflict.
One idea could be a fanfiction where Denji gets transported to a modern-day city outside of his own world. He has to adapt to new technology and deal with a different kind of devil threat. Another could be a story that focuses on Power's past before she met Denji, exploring her time in Hell and how she became the way she is. A third idea might be a fanfiction where Makima is actually a double agent, secretly working against the devils she seems to be controlling.
Another idea is a story where a character from the Chainsaw Man universe ends up in the Naruto world. This could lead to all sorts of chaos as they introduce their unique abilities and concepts. For example, they might try to teach Naruto and his friends about devil contracts in the context of the Naruto world's power system.
One idea could be creating an OC (Original Character) who is a young martial artist from a different part of the world coming to Ip Man's school to learn. This OC could bring in new fighting styles and cultural elements, leading to interesting exchanges with Ip Man and his students.
One idea could be an OC who is a scientist working alongside Hank Pym. They could be developing a new type of Pym Particle with unique properties. For example, instead of just shrinking and growing, it can also change the density of objects. This OC could face challenges like dealing with rival scientists who want to steal their research.
An interesting OC for an Ultimate Spider - Man fanfiction could be a mutant who has spider - like abilities but also some other powers that set them apart. For instance, they might have the ability to communicate with spiders on a telepathic level. This OC could start out as an outcast in society, just like Peter Parker, but their powers are a bit more extreme and they have to learn how to control them. They could initially be seen as a threat by Spider - Man but then they team up to fight a greater evil.
An OC who is a master of disguise could be a great plot. They keep changing their appearance during the show, confusing the other players and creating really interesting and comical situations.
One idea could be a crossover between Spider - Man and an original character (OC) who has the power to manipulate time. The OC could accidentally disrupt the timeline in Spider - Man's world, leading to all sorts of chaos like villains getting released early or important events not happening as they should. This would force Spider - Man to team up with the OC to fix the timeline.
Well, a great plot for a Running Man x OC fanfiction could be that the OC is a world - class athlete who comes to the show to prove that they are the best. Along the way, they form friendships and rivalries with the regular Running Man cast. Or perhaps the OC is an alien who crash - lands near the set of Running Man and is forced to participate in the games to earn their way back home. Also, the OC could be a detective who is investigating a mystery related to the Running Man show and has to join the games to gather clues.
Well, your OC could be a lost reploid from an ancient civilization. This OC might hold the key to a forgotten technology that could either save or destroy the world in the Mega Man X universe. They would have to navigate the politics and battles while trying to figure out their own origin and purpose. Also, an OC that was created by a villain but has a sense of good could be an interesting plot. This OC would constantly struggle between their programming and their new - found moral compass.
One idea could be that the OC is reincarnated as a relative of Peter Parker. This would create an interesting dynamic as they would have an in - built connection to the main Spider - Man character. They could inherit some of Spider - Man's powers in a different way, perhaps through a scientific experiment gone wrong that was related to Peter's own origin.