One common theme is friendship. Just like in the main MLP series, the relationship between Rainbow Dash and the OC often revolves around learning about each other, being there for one another, and growing through their friendship. For example, in many stories, the OC might be new to Ponyville and Rainbow Dash helps them fit in.
Adventure is also a popular theme. Rainbow Dash is known for her adventurous spirit, and when paired with an OC, they often go on exciting quests. It could be anything from finding a lost magical artifact in Equestria to saving the town from a new threat. These adventures not only strengthen their bond but also make for exciting reading.
One common theme is friendship. Given that they are both characters from the MLP universe which highly values friendship, many fanfics explore how their friendship develops. Another theme is competition, as both are pegasi and might compete in flying races or other aerial challenges in the fanfics.
A sense of discovery is also prevalent. The reader discovers new aspects of Equestria, new magical elements, and also discovers more about themselves and their relationship with Rainbow Dash. This can include learning about new flying techniques if the reader is also a pegasus in the story, or just exploring new parts of the land together.
One common theme is friendship development. Since they have different personalities, seeing how they become closer is often explored. Another theme is mutual support. For example, Rainbow Dash might encourage Fluttershy to be more brave, and Fluttershy could help Rainbow Dash be more patient.
Friendship is a very common theme. Since they are both characters from the MLP universe, fanfics often explore how their friendship develops and grows. They might start as acquaintances and become best friends, or they might have some bumps in their friendship that they need to overcome.
Adventure is also a popular theme. They might go on a quest together, like looking for a lost treasure or saving Ponyville from a mysterious threat. This allows for a lot of action and character development. In these types of fanfics, Rainbow Dash's bravery and Pinkie Pie's spontaneity often play important roles.
Another theme is competition. Given their speed - based abilities, it's not uncommon for fanfics to pit Rainbow Dash and Sonic against each other in races or challenges. However, these competitions usually end up with them learning from each other and becoming better friends in the process. It's a way to explore their personalities and how they deal with winning and losing.
Another common theme is adventure. Fanfics often send them on exciting adventures, whether it's exploring a new part of Equestria or going on a quest to find a magical item. Their different skills and personalities, like Rainbow Dash's speed and Fluttershy's ability with animals, play important roles in these adventures. They might also learn something new about each other during the adventure, strengthening their bond.
One common theme is the struggle between two identities. Rainbow Dash has her normal pony self and then the new werewolf aspect which often causes internal conflict. For example, she might worry about how her friends will react or how she can control her new powers.
Friendship is also a major theme. Their relationship is explored in different ways. Sometimes it's about how they support each other during tough times. Like in some fanfics where Scootaloo gets bullied for her lack of flying ability, Rainbow Dash is there to cheer her up and encourage her.
One common theme is failure. For example, Rainbow Dash might fail at a big race or competition, leading to her feeling sad and disappointed in herself.