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 idea could be a crossover with 'The Lord of the Rings'. Picture the Dark Souls characters in Middle - earth, facing off against orcs and other dark creatures. Another could be a crossover with 'Bloodborne'. The gothic and nightmarish settings of both could blend well, with hunters and Dark Souls' warriors teaming up against a greater evil. A third idea might be a crossover with 'Final Fantasy'. The different magic systems and character classes could create really unique and exciting storylines.
A crossover with 'Final Fantasy' would be cool. The magic systems in both could be combined in interesting ways. For example, a Dark Souls 2 mage could learn some spells from a Final Fantasy character. Also, a crossover with 'The Elder Scrolls' series. The vast open worlds of both could create an amazing setting for the fanfiction. The character could explore different regions of Tamriel and use their Dark Souls 2 abilities to survive.
One plot idea could be that the Fire Keeper from Dark Souls is transported to another world in the crossover. There, she has to adapt to new rules and powers. Maybe she meets characters from the other universe who initially mistake her for something else due to her unique appearance and abilities from Dark Souls. Another idea is that she teams up with a character from the crossover world to fight a common enemy that threatens both of their realms. This enemy could be a powerful being that feeds on the essence of different worlds, and their combined knowledge and skills are the only hope to stop it.
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.
One idea could be exploring Yorshka's origin in more depth. Maybe she has a hidden past that involves a powerful being from another realm. Another plot could revolve around her relationship with the player character. For example, they form an unexpected alliance to face a common threat in the Dark Souls 3 world. A third plot idea could be that Yorshka discovers a long - lost power within herself that changes the balance of power in the game's universe.
A possible plot could involve an OC who is a healer with a mysterious past. They find themselves in the middle of the Dark Souls' dark and dangerous world. They start out trying to simply survive but soon realize that they have a greater purpose. Their healing powers attract both the good and the bad, and they must decide who to trust as they navigate through the complex politics and battles of the game's world.
One interesting crossover could be the fusion of the unique combat styles. For example, in RWBY, the characters use their weapons in creative ways, and in Dark Souls, the combat is more methodical and strategic. A fanfiction might have Ruby using her scythe in a way that combines the fast - paced attacks from RWBY with the precise timing and dodging required in Dark Souls. Another aspect could be the world - building. The dark and foreboding atmosphere of Dark Souls could seep into the RWBY universe, creating new and dangerous regions. Characters from Dark Souls might find themselves in Beacon Academy, leading to some interesting cultural clashes and exchanges of fighting techniques.
One idea could be the characters from RWBY ending up in the world of Overlord. They might initially be confused and have to adapt to the new, more dangerous environment. Maybe Ruby could mistake some of the Overlord's minions for Grimm and attack, causing a stir among the various factions in the Overlord world.
One idea could be that the characters from RWBY are transported into the Destiny universe and have to learn to use the unique weapons and powers there. For example, Ruby could be fascinated by the Exotic weapons in Destiny and try to incorporate their technology into her Crescent Rose. Another plot could involve the Guardians from Destiny being sent to the RWBY world to help fight against the Grimm. They would have to adapt to the new environment and team up with the RWBY characters. The third idea is that a powerful enemy from the Destiny universe somehow crosses over to RWBY's world and the combined forces of both universes have to stop it.
Maybe the Persona users' powers start to malfunction in the RWBY world due to the different nature of the place. So they have to figure out how to control their powers again while also helping the RWBY characters in their battles. The RWBY characters could be intrigued by the Persona powers and try to learn from them.