One great example could be a crossover between 'Once Upon a Time' and 'Harry Potter'. Imagine the fairy - tale characters from 'Once Upon a Time' finding their way into the magical world of Hogwarts. Snow White could be a student in the Defense Against the Dark Arts class, learning spells alongside Harry and his friends. Another example is a crossover with 'The Lord of the Rings'. Characters like Regina might be intrigued by the power of the One Ring and get involved in the epic quest in Middle - earth.
A 'Once Upon a Time' and 'Doctor Who' crossover fanfiction would be really interesting. The Doctor could land in Storybrooke and start meddling with the fairy - tale characters' lives. He might try to solve the mysteries of the Evil Queen's curse using his time - traveling knowledge. Also, a crossover with 'Star Wars' could see characters like Emma Swan using the Force in some way. Maybe she discovers she has some Jedi - like powers that help her fight against the villains in her own world.
Character interactions are key. Imagine Stiles from Teen Wolf and Rumplestiltskin from Once Upon a Time having a conversation. It should be both interesting and in - character. The fanfic should also introduce a new and exciting plot that couldn't exist in either show alone. Maybe a new threat that combines the darkness of the Nogitsune from Teen Wolf and the power - hungry villains from Once Upon a Time. Another important aspect is the setting. How will Beacon Hills and Storybrooke interact? Will there be a merge of the two or just portals between them?
I found a really fun crossover fanfic where the villains from Descendants team up with some of the forgotten villains from Once Upon a Time. It's called 'Villainous Alliances'. It shows how they would interact and form plans to take over both their worlds. The character development in this fanfic is quite good as it gives more depth to the Descendants' villains who might seem one - dimensional at first.
Some Reddit communities dedicated to fanfiction might also be a good source. For instance, r/FanFiction. Members often share their favorite stories or even their own works. You can post a request for harem fanfiction there and get some great recommendations.
Some fandom - specific forums or communities might also be a great place to look. For example, if it's related to a particular TV show or movie, the official fan forums often have sections for fanfiction. Members might share their own 'once upon a time future' stories or recommend ones they've read.
One great Stiles 'Once Upon a Time' crossover fanfic is 'Stiles in Storybrooke'. It has an interesting plot where Stiles somehow ends up in the world of 'Once Upon a Time' and has to navigate the magical and often dangerous situations there. He teams up with some of the characters from the show, and the interactions are really engaging.
Well, Tumblr can also be a great place to discover once - upon - a - time female oc fanfiction. There are many blogs dedicated to sharing and discussing fanfics. Some users post their own works, and you can often find reblogs of great stories. Additionally, Reddit has some subreddits related to fanfiction where people might share or recommend female oc fanfiction in a 'once upon a time' style.
One great Teen Wolf and Once Upon a Time crossover fanfiction is 'The Lost Wolf in Storybrooke'. It combines the dark, supernatural elements of Teen Wolf with the fairytale - like world of Once Upon a Time. The story has Scott McCall finding himself mysteriously transported to Storybrooke and having to navigate the new rules and characters there. It's really exciting to see how he interacts with the likes of Emma Swan and Regina Mills.
One common theme is the clash of different worlds. Stiles comes from a world with its own set of rules, and 'Once Upon a Time' has its own magical and fairytale - like rules. So, there's often a theme of adjustment and adaptation. Another theme is the discovery of new powers or abilities. Stiles might find out he has some latent magical abilities in the 'Once Upon a Time' world.
First, choose the two (or more) universes you want to cross over. For example, if it's 'Once Upon a Time' and 'Pirates of the Caribbean', think about how the magic of 'Once Upon a Time' would interact with the swashbuckling world of pirates. Then, decide on a central plot. Maybe a character from 'Once Upon a Time' is accidentally transported to the Caribbean and has to find a way back home. Next, create some rules for how the different elements will combine. Like, will the fairy - tale magic work the same way in the pirate world? And start writing, introduce the characters and the initial situation clearly.
One popular theme is the collision of different magical worlds. For example, characters from 'Once Upon a Time' might cross over into the 'Harry Potter' universe. Another theme could be the exploration of different power dynamics. Characters with different magical abilities meet and have to figure out how to co - exist or compete. And the theme of redemption through cross - over is also common. A character from one story who has made mistakes gets a chance to redeem themselves in a new, crossover setting.