One interesting concept could be the merging of different character personalities. For example, if a character from 'Left Behind' is crossed over with a character from another series, their contrasting beliefs and values can create engaging storylines. Maybe a character who is very religious in 'Left Behind' meets a more skeptical character from another story, leading to debates and growth for both.
Next, start planning your story structure. Decide on the main characters from each side that will be involved in the crossover. Outline how they will meet and interact. For example, if you're crossing 'Left Behind' with a science - fiction series, you might have a spaceship land in the middle of the post - apocalyptic world. Then, think about how the characters will react to this strange new element in their world. This will form the basis of your plot development.
Well, in the 'rwby ruby left behind fanfiction', it might focus on Ruby's character development when she's left behind. For example, it could show her facing new enemies or challenges that she wouldn't have encountered with her team. It could also delve into her emotional state, like feelings of abandonment at first, but then growing stronger and more self - reliant as the story progresses.
One interesting concept could be a crossover with another post - apocalyptic game, like adding characters from Fallout into the Left 4 Dead universe. They could bring their own unique skills and weapons, which would change the gameplay dynamic. For example, a Fallout character might have a Pip - Boy that could be used to detect special items or infected in a different way.
One idea could be a crossover with a post - apocalyptic zombie series. The characters from Left for Dead could find themselves in a different zombie - infested world and have to adapt to new threats and survivors. For example, they might encounter a group that has a very different approach to survival, like a religious cult that believes the zombies are a form of divine punishment. This could lead to conflicts and alliances as the Left for Dead characters try to find their way back to their own world.
Next, come up with a plot. Maybe the Left 4 Dead survivors are transported into the other universe, or vice versa. The plot should be engaging and give a reason for the crossover. You could start with a small event that leads to a bigger adventure. For instance, a strange portal appears in the Left 4 Dead world that sucks the survivors into an anime city filled with new threats and allies.
One possible reason could be that Kushina was forced to leave Naruto due to some external threat she thought would endanger him more if she stayed. For example, if there were powerful enemies after her and she feared they would use Naruto to get to her.
Fanfiction.net is also a great place to search for it. There are many RWBY - related fanfictions on that site. Just use the search function and type in 'rwby ruby left behind' to see if it shows up. However, the quality and content can vary greatly on this site.
In this fanfiction, they might have to face a series of challenges alone. Maybe they'll encounter powerful enemies that they have to defeat without the help of their usual comrades. They could also discover new powers or abilities within themselves during this time of being left behind.