A 'Fairy Tail RWBY fanfic' could also explore a romantic relationship between a character from each series. Imagine Natsu from Fairy Tail falling in love with Ruby from RWBY. Their different personalities and powers would make for an interesting dynamic, and the story could focus on how they overcome the differences between their two worlds to be together.
One idea could be a crossover where the characters from Fairy Tail and RWBY team up to fight a common enemy. For example, they could face a powerful dark mage who has the ability to manipulate Grimm. The Fairy Tail mages could use their magic, while the RWBY teams use their weapons and semblances in an epic battle.
Well, you could write a 'a fairy'a tail fanfic' about a time - travel adventure. Maybe the characters go back in time to prevent a great disaster that was hinted at in the original series. Or perhaps a story where the Fairy Tail guild has to team up with their arch - enemies to face a common, much greater threat. And a simple but interesting idea could be a day - in - the - life story of one of the guild members, showing their normal routine as well as some unexpected events.
You could write a 'Fairy Tail Fanfic' where the magic system is completely different. For example, instead of having different types of elemental and non - elemental magic, there's only one type of magic but different levels of mastery. Or a fanfic that focuses on the relationships between the guild members in a romantic aspect. Like a love triangle between Gray, Juvia, and a new character.
One idea could be that the Fairy Tail guild members are transported to the RWBY world. They could team up with Team RWBY to fight a common enemy like a new type of Grimm that is resistant to normal Huntsmen and Huntresses' attacks but vulnerable to Fairy Tail's magic. For example, Natsu's fire magic could be really effective against ice - based Grimm.
Another plot could involve a magic - based tournament where teams from both Fairy Tail and RWBY participate. This would allow for battles between different characters, like Natsu from Fairy Tail facing off against Yang from RWBY. The different fighting styles and power sources would make for exciting match - ups and also a chance for the characters to learn from each other.
One idea could be that the Fairy Tail guild members get transported to the world of RWBY. They could team up with the RWBY teams to fight against a common enemy like a powerful new Grimm that is resistant to normal attacks. The mages from Fairy Tail could introduce their unique magic to the RWBY characters, like Natsu's fire magic which could be useful in burning through Grimm hordes.
Another interesting idea is to set the fanfic in an alternate universe where Fairy Tail is more of a school for mages. The main character, a transfer student, quickly becomes popular and gathers a harem. Each member of the harem could represent a different type of magic or personality within the school, like a shy water mage, a brash fire mage, and a wise wind mage.
A crossover with 'Naruto' could also be cool. Imagine the Fairy Tail guild members in the Hidden Leaf Village. They could participate in the Chunin Exams, and their magic would be a new type of jutsu. There could be battles between Fairy Tail mages and ninja, like Natsu vs Sasuke, which would be an epic showdown of fire - based powers.
Well, one interesting idea could be the return of the dragons bringing new powers to the Fairy Tail wizards. Maybe they bestow unique magical abilities that help the guild face even greater threats. Another idea might be the re - establishment of old bonds between the dragon slayers and their dragon parents or mentors, leading to some really heart - warming or intense emotional moments.
A more complex idea could be that the magic in the Fairy Tail universe somehow affects the Omnitrix, causing it to mutate and create new and unexpected alien forms. This would bring in elements of both worlds in a very unique way, and the characters would have to figure out how to deal with these new forms and the potential threats or benefits they bring.
One idea could be to focus on a Celestial Dragon that has been banished from its own realm and ends up in the Fairy Tail world. It could form an unlikely bond with a Fairy Tail member and learn about friendship and loyalty. Another idea is to explore the origin of the Celestial Dragons in the context of the Fairy Tail universe and how they came to be associated with the Celestial Spirit magic. Maybe a young Celestial Dragon is being hunted, and the Fairy Tail guild decides to protect it, leading to an epic adventure.