Kai could also go on a journey of self - discovery. He sets out to find his true place in the Avatar world. Along the way, he meets various characters who teach him different things about the world, the elements, and himself. He might encounter a wise old hermit who gives him cryptic advice that he has to figure out how to apply to his life.
Another storyline could involve Kai's relationships. He could fall in love with an OC from a different tribe. This would create a lot of drama as their tribes might have some sort of feud or different values. They would have to fight against the odds to be together, and Kai might have to prove himself to her tribe to gain their acceptance.
To develop Kai's character, start with his backstory. Decide where he comes from, his family situation, and any major events in his past that shaped him. For instance, if he grew up in a poor family, he might be more resourceful and determined to make a better life for himself. His appearance can also reflect his character. If he has long, unkempt hair, it could show that he's a bit of a free spirit.
One idea could be to create a male OC who is a skilled mechanic. He could start off as an ordinary worker in one of the Gundam 00 facilities. But then, through a series of events, he discovers a hidden ability within himself related to the Gundam technology. Maybe he can communicate with the Gundam on a deeper level than anyone else. This could lead to him being recruited into a special team that deals with high - risk missions. He would have to face challenges not only from the enemies but also from within the team as some might be jealous of his new - found abilities.
One idea could be an OC who is a long - lost relative of the Russo family. They come to town with a special power that the Russos don't have, like the ability to control time. This could create all sorts of interesting situations, such as going back in time to prevent a major disaster that was going to happen to the family in the future.
Perhaps an OC Lannister who is a talented healer. In a world full of wars and battles in Game of Thrones, a healer Lannister could be an interesting addition. They might have to deal with the moral dilemma of healing both their own family's enemies and allies. They could also have a secret love affair with a member of another house, which would add a layer of drama.
The male OC Baratheon could also be a bastard son who has been living in exile. He returns to Westeros with a group of loyal followers he has gathered over the years. His main goal could be to claim a small piece of land for himself and his men, but he soon realizes he has to navigate the complex web of politics and allegiances in order to survive.
Maybe the male OC is a huge Lantern fan and he creates his own makeshift Lantern ring. It doesn't work like the real ones at first, but through his determination and some help from a mysterious mentor figure, he manages to unlock its true potential. This could lead to a story of self - discovery and growth within the Young Justice universe.
One idea could be to create an OC (Original Character) who has a unique multimagic ability that is related to the elements but in a different way than the existing characters in Fairytail. For example, instead of controlling fire, water, etc. directly, the OC can manipulate the energy within those elements. They could join Fairytail and face challenges that test their new abilities and their loyalty to the guild.
One idea could be to create an OC (Original Character) who is an Element Dragon Slayer with a unique element, like shadow. The fanfiction could start with the character's discovery of their powers in a small, forgotten village. They then embark on a journey to find their dragon parent, facing various challenges along the way, including battles with dark guilds who want to use their power for evil.
For a fanfiction, perhaps the OC firebender is from a small, unassuming village in the Fire Nation. They have a unique form of firebending that is more about control and precision rather than brute force. The OC could be on a quest to prove to the Fire Lord that this new style of firebending is better and more effective. Along the way, they face challenges from traditionalist firebenders who think their way is the only right way. They also cross paths with the Avatar's group, and there's an exchange of ideas between them. Eventually, the OC might use their unique skills to help the Avatar in a crucial battle.
One idea could be a male OC who is a waterbender from a small, isolated tribe. He discovers he has a unique ability to control ice in ways others can't. He then sets out on a journey to learn more about this power and ends up getting involved in the larger events of the Avatar world, perhaps helping the Avatar in some way.