Fans of the Kingdom Hearts series have begun to speculate on what the future of the series will be, focusing on Kingdom Hearts' original characters and story. However, what's certain for KH4, and any other future games, are Disney worlds. The Disney-themed worlds make up the bulk of KH gameplay, and are an iconic part of the franchise.

There's plenty of possibilities for Kingdom Hearts 4 Disney worlds, including newer movies and some that went overlooked in Kingdom Hearts 3. Each has their own potential for gameplay mechanics, new forms, and new enemies for Sora and friends to fight.

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Princess and the Frog

Tiana and Naveen from Disney's Princess and the Frog

The world of Disney's The Princess and the Frog has been a popular fan request for inclusion in Kingdom Hearts for years. It's certainly a world with a lot of potential: The visual style of the movie is gorgeous, and would translate well into a stylized Kingdom Hearts world. Tiana and/or Naveen would be fun party members, and there could be segments involving their human forms and animal forms.

Doctor Facilier would make a great antagonist for a Kingdom Hearts world, with his voodoo magic and "friends from the other side." Heartless enemies themed after dark spirits and other beings from the bayou could populate the world. A boss fight featuring Facilier would be colorful, fun, and sure to have fantastic musical accompaniment.

While the movie's plot may need to be abridged for gameplay purposes, it has plenty of locations to explore: New Orleans, the Bayou, and maybe even the "other side." Tiana's story of determination and realizing her dream, even through difficulties, fits well in the overall optimism of the Kingdom Hearts series.

After Kingdom Hearts 3 stuck to 3D animated features for its worlds, it would also be nice to give some recognition to the last major traditionally animated feature from the studio.

Moana

Moana has been another popular fan pick for a new world; some fans have presented it as a world for Kairi specifically to journey through. Kairi's character does have an ocean-like theme, and the idea of her going on her own journey is appealing, especially since Kingdom Hearts: Melody of Memory didn't actually feature her doing much. As a Princess of Heart, it would also be great for her to have opportunities to interact more with other princesses.

The world of Moana would most likely involve a lot of exploration and sailing, similar to the Caribbean in Kingdom Hearts 3. There could be battles on water and land with aquatic Heartless, and perhaps collectibles to find in the vast world. There'd be a lot of exploring to do in between plot cutscenes.

Moana and Maui would make for great party members; both are strong and competent. Maui's hook could provide inspiration for the world's Keyblade variant. The world's boss battles could include both Tamatoa and Te Ka for some cinematic fights.

Coco

Coco is a heartfelt and visually stunning movie, and the Land of the Dead would be an excellent Kingdom Hearts world. The theme of carrying on someone's memory fits in perfectly for the franchise — Kingdom Hearts: Chain of Memories and Kingdom Hearts 2 especially represent this. Considering Sora has technically died multiple times at this point, it also makes sense for him to end up here, perhaps with his own new skeleton look.

The "alebrijes," spirit guide animals, could provide inspiration for enemies or allies. Dream Eaters are similarly colorful animal guides, who could make some sort of return in Kingdom Hearts 4, especially after their new plot relevance. Ernesto De La Cruz is more monstrous in morals than form, but he would likely have one of the Heartless transformations common in the series.

The bright colors and fantastical architecture of this world would be a blast to play through, and Sora and Miguel could end up back in Santa Cecilia for part of the world's story. Between Coco's story and Kingdom Hearts' earnestness and heartrending soundtrack, this world would be a sure tear-jerker.

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Wreck-it Ralph

Wreck-it Ralph's Game Central Station appeared as a world hub with multiple smaller worlds in Kingdom Hearts Union X, and Ralph himself was a summon in KH3. Considering KHUX's major plot relevance, especially now after its closure, it's not too implausible that the world will reappear in a full 3D game.

The residents of this world would have some fun interactions with Sora and his crew, especially with Sora's obliviousness towards being a video game character himself. Similarly to KH3's Toy Box, there are opportunities for some meta jokes in the setting.

The party would travel between the various game worlds and fight Cybugs, Heartless, and maybe even a combination of the two. King Candy's monstrous Cybug form would make a great boss battle for the world. With regards to KH lore, the elements of Data and Bug Blox would likely make a re-appearance in this world.

Disney Parks

Haunted Mansion

Disney's theme parks haven't received much representation in Kingdom Hearts, which makes sense as they're harder to work with than a movie. However, many rides have their own lore and creative potential. The Haunted Mansion, for instance, could make for a world all its own. Ghostly enemies and a built-in soundtrack would make for a fun, spooky experience. It might be visually similar to Halloweentown. World plots may be a bit looser and require some artistic license, but that makes it all the more interesting.

A sort of variation of a theme park would be an interesting world in general-- Prankster's Paradise in Dream Drop Distance and Disney Town in Birth By Sleep were similar concepts. Considering the vast Disney movie catalog, it's unlikely that the parks will receive attention before more movies, but fans of the parks would definitely be pleased to see it in game form.

It will be a long time before any new Kingdom Hearts games, let alone a new numbered title, will be released. That leaves plenty of time for fans to speculate on new worlds. While the focus is on the franchise's original lore right now, the Disney crossover elements certainly won't be going anywhere.

Kingdom Hearts 4 is rumored to be in development.

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