Another concept could be a crossover of the moral systems. In Red Dead Redemption, there's the good and bad karma system, and in Infamous, there's the hero and villain path. A story could explore how a character from one game's system would fare in the other's world. For example, a good - karma Red Dead character suddenly in the Infamous world having to deal with moral choices there.
One idea could be that the protagonist from Infamous somehow gets transported to the world of Red Dead Redemption. Maybe they have to adapt to the old - west setting and deal with outlaws while also trying to find a way back home. Their electrical powers would be a huge shock to the cowboys and bandits.
A possible fanfiction idea is that a group of characters from both games are brought together by a mysterious force. The characters from Red Dead Redemption, with their gunslinging skills, and the characters from Infamous, with their superpowers, have to team up to fight a common enemy. This enemy could be a powerful new threat that neither group could handle alone, like a powerful demon or a corrupt government entity.
Well, a cool crossover fanfiction idea could be with 'The Witcher'. Geralt could find himself in the world of Red Dead Redemption, hunting monsters in the American frontier. Or, for a more comical crossover, think about a crossover with 'SpongeBob SquarePants'. SpongeBob and Patrick end up in the wild west and their naivete causes all sorts of chaos among the outlaws. Also, a crossover with 'Harry Potter' could be interesting, with wizards and witches showing up in the world of Red Dead Redemption and causing a stir with their magic.
One idea could be a fanfiction about an alternate ending where the main character chooses a different path. For example, instead of following the main storyline's conclusion, they decide to start a new life away from all the chaos. Another idea might be a story that focuses on a minor character from the game and gives them a more in - depth backstory and their own adventure. Maybe a story about a young outlaw who is trying to make a name for himself in the world of Red Dead Redemption.
One idea could be exploring the backstory of a minor character in the game. For example, the life of a random outlaw in the gang before they joined. Another could be a what - if scenario, like what if Arthur Morgan didn't get sick. And also, you could write a fanfiction about the relationship between different characters, such as Dutch and Hosea when they were younger.
One idea could be that the main characters from both games, Cole from Infamous and Alex from Prototype, team up to fight a common enemy that threatens both their worlds. Maybe a powerful virus that is mutating people in the Infamous universe and also causing chaos in the Prototype world.
Maybe a crossover with a character from a post - apocalyptic game like Fallout. Cole could find himself in the wastelands, having to adapt his powers to the new environment and deal with raiders and mutants. He might also have to figure out how to recharge his powers in a world without modern infrastructure.
Maybe there's a time - travel aspect. A character from Infamous travels back in time to the era of Red Dead Redemption. They bring with them their knowledge of modern technology and superpowers, which completely disrupts the balance of the old - west. The character has to decide whether to use their abilities to change history or just survive in this new, dangerous world.
Another popular theme is the combination of different types of magic or supernatural elements. If it crosses with a fantasy world like 'Harry Potter', seeing how the magic from that world interacts with the more grounded world of Red Dead is fascinating. The spells and potions in Harry Potter's world can be used in unique ways within the context of Red Dead Redemption 2.
One idea could be a crossover with the Alien franchise. Picture Isaac Clarke in a derelict Alien ship, facing both Necromorphs and Xenomorphs. The different types of terrifying creatures could create a really intense and unique horror scenario.
You could do a crossover with 'Castlevania'. The gothic horror elements of 'Castlevania' would blend well. Dracula could be a powerful killer, and the heroes from 'Castlevania' could be survivors. The survivors might have new abilities like using holy water or magic spells against the killers. It would also be interesting to see how the 'Dead by Daylight' maps would be transformed with the addition of 'Castlevania' - like architecture and elements.
One idea could be a story where characters from 'Dead or Alive' cross over into a post - apocalyptic world. They could use their fighting skills to survive against new and dangerous enemies. Another idea is a crossover with a fantasy realm, and the 'Dead or Alive' characters have to adapt to magic and mythical creatures. For example, Kasumi might learn to use magic spells while still relying on her ninja skills.