Kingdom Hearts fans are currently enduring the long wait until the series returns. After Kingdom Hearts 3 and its DLC wrapped up the Dark Seeker Saga, the community was left with the final stretches of the two KH mobile games and a few cutscenes in the spin-off rhythm game Melody of Memory to tide them over. Square Enix has made it clear that the franchise is not resting on its laurels, as there are supposedly multiple Kingdom Hearts games in development, and a 20th-anniversary celebration is on its way next year. Even so, it feels like the next main installment is a long way off.
Luckily for the fanbase, Kingdom Hearts loves to hint at where it’s going next. Kingdom Hearts 3 wasn't subtle about teasing future storylines, including where the cast is headed next and for what reason. Kingdom Hearts Union χ also revealed more about what will likely be the antagonist of the upcoming saga. Between that and Melody of Memory directly leading into Riku's pursuit of Sora in a new dimension, it feels like fans have been given a pretty clear picture of where Kingdom Hearts 4 is headed.
The Setting of Upcoming Kingdom Hearts
One of the main hints fans have to go off of regarding the upcoming Kingdom Hearts sequel saga is its new location. Teased in Kingdom Hearts 3 and confirmed by Melody of Memory, Kingdom Hearts' future will take place in a parallel reality called Quadratum. This place has been referred to as a world of fiction parallel to Kingdom Hearts' own reality, so whether this means anything in particular besides some of Kingdom Hearts' Worlds coincidentally reflecting Quadratum is another matter entirely. It's not even clear if Quadratum will follow the same separate Worlds structure as normal Kingdom Hearts, as presumably, it has a different history than the once-united Worlds fans know.
This new setting will also come with some new characters, again teased by Kingdom Hearts 3. Sora will be rendered indisposed somehow, and Riku will be busy searching for him. A city that resembles The World Ends With You's Shibuya seems to be involved. However, the real protagonist of the next major Kingdom Hearts game will probably be Yozora, the bonus boss and Riku lookalike introduced in KH3 and detailed by the Re Mind DLC. He may not look the same as he did in Kingdom Hearts 3, and his circumstances may be different from the Verum Rex game featured in the Toy Story world, but he will still probably serve as the new main character, assisting what members of the old cast show up in saving Sora and fighting the new forces of darkness.
Kingdom Hearts' Upcoming Story
There are a number of other dangling plot threads that Kingdom Hearts 4 is primed to pull on. The most obvious one is the impending return of the Foretellers, the Master of Masters, and the Black Box. It seems like MoM and his students will take the roles of the main villains in the upcoming games, with the Master’s plan to have his group embody the remaining Darknesses from the χ-Blade’s formation likely bearing fruit. The whereabouts of all of them, especially the still-absent Ava, will also probably be explained.
There are a few more plot threads to wrap up, even if they don’t appear in Kingdom Hearts 4 proper. The Birth By Sleep trio has set out to help scour the Worlds for Sora, but the presence of Ventus’ Chirithy could send their journey on another path towards the Union Cross Keyblade wielders. Kairi’s continued training is practically begging for a proper KH side game focused on her. Further, the mysterious Subject X brought up in KH3, as well as the girl encountered in the Final World, has yet to be explained and seems to exist purely for future storylines. Kingdom Hearts is far from over, and fans will be keen to see what exactly the future holds when the series picks back up.
Kingdom Hearts 4 is not confirmed to be in development.