Quadratum is a mysterious world teased in Kingdom Hearts 3 and will be revealed even further in Kingdom Hearts IV. But what is this strange real-life-looking world for Sora? We explore everything we know below.
In the trailer for Kingdom Hearts IV, Sora meets Strelitzia, a Dandelion keyblade wielder from the time of the foretellers, who was previously killed in the mobile game Union X. She tells our hero that Quadratum “is similar to an ‘afterworld’. Sora was placed inside Quadratum after using the Power of Waking too many times to alter the fates of his friends and saving Kairi for a final time.
In an interview with Famitsu, series director Tetsuya Nomura gave one more detail about Quadratum. He confirmed that it’s not in the realm of light, darkness, or nothingness (where the last fight with Xemnas in Kingdom Hearts 2 took place). “Quadratum is a world behind the scenes that is different from reality, a fictional world,” said Nomura from a rough Google translation. “However, from the perspective of the inhabitants of Quadratum, the world is real.”
During the same interview, Nomura also confirmed that Quadratum is not connected to either Shibuya from The World Ends With You or Strangers of Paradise: Final Fantasy Origin.
However, during a cutscene in Kingdom Hearts: Dream Drop Distance, Square Enix teased a possible meeting in Shibuya with Neku. The redhead hero said, “See you in Shibuya,” and Sora agreed. This leads to a possible team-up in Kingdom Hearts IV.
Also, a different number is presented on the Shibuya Crossing tower in the Kingdom Hearts 3 secret ending from The World Ends With You, so Nomura wouldn’t be wrong.
At the end of the rhythm action entry of the series Melody of Memory, Riku decides to travel to Quadratum to save his friend Sora, so we know he won’t be alone.
Finally, Quadratum seems to be an early world that Sora will visit in Kingdom Hearts IV. Nomura has confirmed that there will be multiple worlds in development and that the apartment we see in the debut trailer will be a base for the beginning of the game. We can see Quadratum being a world you go back to regularly, like Kingdom Hearts’ Traverse Town or Kingdom Hearts 2’s Hollow Bastion/Radiant Garden.