In many fanfictions, Red X could be Robin. Maybe he has some secret motives or a hidden side that leads him to take on the Red X persona. It could be a way for him to operate outside the normal constraints of the Teen Titans while still being involved in the action.
Another possibility in fanfiction is that Red X is a completely new character created within the writer's imagination. This character might have a connection to the main Teen Titans characters, like being a long - lost relative of one of them who has a vendetta against the Titans for some past event. They use the Red X identity to infiltrate and cause chaos.
Some fanfictions might also suggest that Red X is an alternate - timeline version of one of the existing characters. For example, if something went horribly wrong in a particular timeline for Beast Boy, he could become Red X as a result of his disillusionment with the Titans and his new - found darker side.
One popular plot is the revelation that Red X is a double agent. He's been working for the Titans' enemies all along but has a change of heart when he gets to know the Titans better. This often leads to a redemption arc for the character.
Red x fanfiction could refer to fan - created fictional works related to a character or concept named 'Red x'. It might involve stories, scenarios, or alternate universes centered around this entity within the realm of fanfiction.
However, it could be that there's someone else pulling the strings. Maybe a new villain has hired Red X to capture Starfire. This new villain could be the real antagonist, with Red X just being a tool. In some fanfictions, it's common to have a hidden mastermind behind the obvious bad guy. So, it might not be as straightforward as just Red X being the bad guy all on his own.
Obviously, Red X would be the main antagonist as he is the one doing the kidnapping. But there could also be other antagonists in the background. For example, if Red X was working for someone else, that person could also be an antagonist. Maybe a powerful intergalactic criminal who wants Starfire's powers for his evil plans.
Well, obviously Red and Yellow are the main characters. Red is often depicted as a bold and adventurous character, while Yellow might be more of a gentle and kind - hearted one. They play off each other in the story.
Red X might be motivated by revenge. Maybe Starfire had previously thwarted his plans, and he's getting back at her by tying her up with the slime.
Another idea is that the main antagonist is actually an aspect of Starfire herself, represented by the 'Oozing Red X'. It could be some sort of dark side of her that has manifested in this form. So she's not just fighting an external foe, but also this internal struggle that is personified by the 'Oozing Red X'.
It could be about them teaming up to fight a common enemy. Maybe an otherworldly villain that threatens both their worlds.
It could start with Red Hood on a mission in Gotham when he witnesses a strange object falling from the sky. When he investigates, he discovers it's Supergirl. She's disoriented from a battle she had in space and Red Hood has to decide whether to help her or be wary of this powerful new arrival.
One possible motive could be to use her as a bargaining chip. Maybe against the other Teen Titans, like Robin or Beast Boy. Red X might want something in return for her safe release.