A common theme is the crossover of different worlds. Since Fairly OddParents has a magical, comical world and Danny Phantom is set in a more spooky, ghost - filled world, the clash and combination of these two is often explored.
Friendship and teamwork is another big theme. Many fanfictions show how characters from both shows team up, like Danny and Timmy working together to solve problems that span across their two very different worlds. It's about how they overcome their differences and use their unique abilities to achieve a common goal.
There could be a fanfiction where the characters from both shows meet at a special supernatural convention. Danny is there to learn more about different types of ghosts and Timmy is there because his fairies thought it would be a fun place to take him. They end up sharing their experiences and helping each other out in various ways.
A popular one is 'When Fairly Odd Meets Phantom'. This fanfiction delves deep into how the magical fairies from Fairly OddParents would react to the ghosts in Danny Phantom's world. It's filled with humorous situations and some unexpected alliances between the characters.
First, get to know both shows really well. Watch all the episodes, understand the characters' personalities, powers, and the rules of their respective universes. For example, in 'Fairly OddParents', the fairies can grant wishes but there are always consequences. In 'Danny Phantom', Danny has his ghost powers and a set of enemies. Then, come up with an interesting concept like a crossover event or a new adventure for the characters. Maybe something like Danny getting lost in Fairy World.
One common theme is self - discovery. The oc characters often have to figure out who they are and what their place is in the magical world of Dimmsdale. Another theme is friendship, as they usually form bonds with the existing characters like Timmy.
The exploration of new powers and abilities is common too. In a crossover with 'Avatar: The Last Airbender', the fairies' magic could be compared and combined with bending. This allows for new and exciting scenarios where the characters discover how their powers can either complement or conflict with each other.
One common theme is the Tooth Fairy's relationship with the other magical characters in The Fairly OddParents universe. For example, how she interacts with Cosmo and Wanda.
One common theme is friendship. For example, stories might focus on Timmy's friendship with his human friends like Chester and AJ, and how they get into and out of various adventures together. Another theme could be the relationship between Timmy and his fairy godparents. There are fanfics that explore how they learn to understand each other better over time.
Love and friendship are common themes. Their relationship, whether it's a budding romance or a deep platonic bond, is often explored.
One common theme is the struggle between good and evil within Danny. It often shows how his normal self battles his evil side. Another theme is the impact on his relationships. His friends and family have to deal with this new, dangerous Danny.
One common theme is family. Since they are siblings, a lot of fanfics explore their family bond, like how they rely on each other and protect one another. Another theme is secrecy. Danny has to keep his ghost identity a secret, and Jazz often gets involved in that secrecy, either by helping him keep it or by accidentally finding out. Growth is also a theme. As the story progresses, both Danny and Jazz grow as characters, both in their personal lives and in dealing with the supernatural elements around them.