Another plot could be that the OC is an apprentice of an enemy clan. Sub Zero is sent to spy on the clan and meets the OC. The OC is different from the others in the clan, being more kind - hearted. Sub Zero sees this and decides to protect the OC from his own clan's wrath, leading to a complex relationship.
For Scorpion x Sub Zero fanfiction, consider a plot where a powerful sorcerer creates illusions that make them see their worst nightmares involving each other. This causes a huge rift between them, but as they start to realize that these are illusions, they join forces to defeat the sorcerer. Another plot could be set in a post - apocalyptic world where they are the last two warriors left. They have to combine their skills to survive and rebuild their world. Also, a story where they are both haunted by the ghosts of their past actions. They meet in a spiritual realm and must confront these ghosts together. Through this shared experience, they develop a new - found respect for each other.
One interesting plot idea could be exploring the backstories of the characters in more depth. For example, delving into how they got their powers in this Sub Zero setting. Another could be a new villain emerging and the team having to adapt their fighting styles.
A plot could involve Sub Zero training Female Smoke in some new combat techniques. During the training, they develop a mutual respect and a deep friendship that might turn into something more romantic as the story progresses. In this fanfiction, their different fighting styles and abilities could create some really exciting action scenes.
Maybe in the fanfiction, there's a magical or technological accident that swaps their powers for a while. Scorpion has to deal with Sub - Zero's ice powers and vice versa. This leads to a lot of comical and also challenging situations as they try to adapt to the new powers while still facing their usual foes.
The human OC could be a relative of an important figure in the vampire - hunter world. Kaname wants to use her to gain an advantage in the power struggle, while Zero wants to protect her from being used. The OC, in the meantime, is trying to figure out her own place in this strange world. She might start to develop feelings for both Kaname and Zero. As the story unfolds, she discovers secrets about her family that tie her even closer to the conflict. Kaname and Zero then have to decide whether their feelings for the OC are more important than their long - standing enmity.
One idea could be a story where Sub - Zero and Kitana are forced to team up against a new, powerful enemy in Outworld. They start off distrusting each other due to their different loyalties, but as they face challenges together, they begin to respect and rely on one another.
One idea could be that the patient zero OC has a unique ability to heal others despite being the origin of a disease. This creates a moral dilemma within the story as people are both afraid and in need of their power.
One idea could be that the OC is a new student at the academy where Tabitha is. They accidentally cross paths during a magic experiment gone wrong. Tabitha initially sees the OC as a nuisance but gradually discovers they have a unique magical ability that could help her in her own goals. For example, the OC might be able to communicate with magical creatures that are crucial to a mystery Tabitha is trying to solve.
One idea could be a male OC who is a powerful mage from a far - off land arriving at the Tristain Academy. He could have unique magic that no one has seen before, like the ability to control time on a small scale. This would create interesting interactions with the main characters, especially Louise. Another plot could involve the male OC being a spy from a rival country, but gradually falling in love with the world of Halkeginia and having to choose between his loyalty to his homeland and his new - found friends.
You could create an OC who is a master of illusions. This character could use their powers to deceive both enemies and allies, and their backstory could involve being an outcast from their own illusionist clan because they refused to use their powers for evil. In the Re:Zero world, they could help Subaru by creating diversions during battles or by using illusions to uncover hidden truths.