It's hard to say exactly. It could potentially change the entire story arc and character development.
Well, if it never happened, the plot would likely take a completely different direction. Maybe some characters' motivations and relationships would be altered, and the conflicts and resolutions could be very different from what was originally envisioned.
A Kingdom Hearts fanfic might be considered cumbersome if it has overly complex plotlines. For example, if the author tries to incorporate too many characters from different parts of the Kingdom Hearts universe all at once, it can become confusing. Also, if the writing style is overly wordy and filled with long, convoluted descriptions that don't really add to the story, it can make the fanfic cumbersome.
First off, think about what kind of story you want to tell in the Kingdom Hearts universe. Maybe it's a new adventure for the main characters or a side story about a minor character. Make sure your writing style matches the tone of the original series and keep the magic and fantasy alive throughout.
It might be seen as a fanfic because it combines elements from various Disney and Square Enix franchises in an unconventional way, appealing to fans' imaginations and creative reinterpretations.
The fanfic often plays with the different powers and abilities. For example, the keyblades in the MLP world are a unique concept. The ponies might use them in ways different from how they are used in Kingdom Hearts, adding a new dimension to the story. Also, the magic in MLP and the magic in Kingdom Hearts can be combined in creative ways in these fanfics. They might create new spells or ways of fighting that are unique to this crossover.
One common theme is self - discovery. Since the OCs are new to the Kingdom Hearts world, they often have to figure out who they are and what their place is. Another theme is friendship, as they usually team up with the main characters from the game and form bonds. Adventure is also a big theme, as they travel through different Disney - inspired worlds.
Some 'kingdom hearts fanfic' are centered around the Keyblades themselves. They might explore the origin of different Keyblades or the hidden powers within them. There could be a story where a new Keyblade is discovered, and it has a unique connection to an ancient power. This kind of fanfic often dives deep into the lore of the Kingdom Hearts universe.
The unique feature is the combination of different powers. In 'rwby kingdom hearts fanfic', you can see RWBY characters using keyblade powers or Kingdom Hearts characters using Dust. For example, Weiss could use ice Dust with keyblade attacks.
Another theme could be the idea of self - discovery within the context of the 'Kingdom Hearts' universe. The characters might be coming to terms with their sexual orientation while dealing with the various challenges and adventures in the game world. This can add an extra layer of depth to the characters' development. Also, some fanfics may have themes related to the acceptance or rejection of such relationships within the 'Kingdom Hearts' society, which can create interesting storylines.
One main theme is friendship. Just like in the original Kingdom Hearts and Pokemon, characters form strong bonds. For example, Sora might team up with Ash and they learn to trust each other.
One great fanfic about Roxas and Xion is 'The Bond Beyond'. It beautifully explores their relationship as they struggle with their identities within the Kingdom Hearts world. The author does an amazing job of delving into their emotions and the unique connection they share.