One idea could be a crossover where the characters from RWBY enter the Dark Tower universe and have to face its unique challenges. Maybe Ruby could use her scythe skills to fight off the creatures that lurk around the Dark Tower.
A possible fanfiction plot could involve the Dark Tower's magic affecting the RWBY characters in unexpected ways. For example, Weiss might gain new ice - based powers related to the strange magic of the Dark Tower, and she has to learn to control them while also dealing with the tower's mysteries.
In some 'rwby dark ruby fanfiction', there might be the idea of Ruby being corrupted by an ancient evil force. This could lead to her having to fight against her own nature as she is slowly turned into something she hates. It can also show how her friends try to save her from this dark path, which makes for a really engaging story.
Another plot idea might be an OC who is on a quest to find a long - lost relative who was taken by the Crimson King. This OC could team up with the main characters like Roland. Along the way, they face challenges like dealing with the various creatures in the wastelands and trying to decipher the riddles left by the Man in Black.
One idea could be that the characters from RWBY are transported into the Dark Souls universe. They have to adapt to the harsh and unforgiving world, facing the difficult enemies and complex level designs. For example, Ruby could use her scythe skills in the Dark Souls combat system, but find that the enemies are much more resilient than the Grimm she's used to.
One interesting 'Dark Tower' fanfiction could be about exploring the backstory of a minor character. For example, a story that delves into the early life of a gunslinger before they joined the ka - tet. It might show their training and the events that led them to the path of the Beam.
There might be a fanfiction that delves deeper into the backstory of some of the minor characters from the original 'The Dark Tower' series. It could explore how they came to be in the situations they are in and what their true motives are. This adds more depth to the overall world of the Dark Tower.
Maybe the fanfic could explore the concept of the bonfires in Dark Souls in the RWBY universe. The characters could find special areas that act like bonfires, where they can rest, regain health, and upgrade their weapons. They could also meet strange characters at these bonfire - like places, similar to the NPCs in Dark Souls who give quests or useful information.
Ruby would be really interesting. Her optimism and determination in RWBY could be a great contrast to the often dark and foreboding nature of the Dark Tower universe. She could inspire the characters there with her can - do attitude and also learn a lot from the more cynical or world - weary characters in the Dark Tower world.
One interesting idea could be a crossover of different timelines within RWBY. For example, characters from the past meet the current ones and have to deal with the differences in their worlds. Another could be a crossover of different teams in unexpected ways, like Team RWBY having to team up with a rival team to face a common enemy that is more powerful than any they've faced before. And sometimes, there are crossovers that involve alternate versions of the characters, where their personalities or abilities are slightly different, which can lead to very unique and engaging storylines.
One idea could be exploring his past before he became the Man in Black. Maybe he had a family or a different life that led him down this dark path. Another plot could involve him having a change of heart due to an unexpected encounter, like meeting a child with pure innocence that makes him question his actions.
One interesting fanfiction could be about exploring the backstories of the characters more in - depth. For example, delving into the past of Roland before his journey in the movie. It might show his early training and the events that shaped him into the gunslinger we see in the film.