General Prompts:
* Reverse the roles: What if the main character was the villain instead? What if the villain was the hero?
* Time travel: What if the characters were transported to a different time period? What if they could change the past?
* Alternate universe: What if the characters lived in a different world? What if they had different jobs or relationships?
* What if...?: What if the characters never met? What if they died in the original story? What if the hero chose a different path?
* Lost episode: Write a story that takes place between two episodes of the original work.
* Explore a side character: What is the backstory of the character's best friend? What are their motivations?
* Forbidden love: What if two characters who should never be together fell in love?
* Unexpected pairing: What if two characters who were rivals or enemies in the original story fell in love?
* Reimagine the ending: What if the original ending was different? What if the characters chose a different path?
Specific prompts:
* Harry Potter: What if Harry was sorted into Slytherin? What if Voldemort never killed his parents? What if the Triwizard Tournament was held differently?
* Star Wars: What if Anakin Skywalker never turned to the dark side? What if Luke and Leia never met? What if the Empire won the Galactic Civil War?
* Game of Thrones: What if Daenerys Targaryen never came to Westeros? What if Jon Snow wasn't a Targaryen? What if Tyrion Lannister had become king?
* The Lord of the Rings: What if Frodo had failed to destroy the One Ring? What if Aragorn had never left Rivendell? What if Gandalf had been killed by the Balrog?
* Supernatural: What if Sam and Dean Winchester were separated at birth? What if Castiel had never met the Winchesters? What if the apocalypse never happened?
* Doctor Who: What if the Doctor never met Rose Tyler? What if the Doctor had a different companion? What if the Master won the Time War?
* The Avengers: What if Captain America never went back in time? What if Iron Man had never been captured by the Mandarin? What if Thanos had won the battle for Earth?
Bonus:
* Create a challenge for yourself: Write a story in a specific genre, like romance, horror, or sci-fi.
* Write a story based on a fan art: What story does the art inspire?
* Write a story based on a song: What story does the music tell?
Remember:
* Have fun and be creative! Fanfiction is a great way to explore your favorite worlds and characters in new ways.
* Be respectful of the original work. Try to stay true to the characters and the world you are writing about.
* Be original. Don't be afraid to add your own twist to the story.
Happy writing!