For the 20th Anniversary event of Kingdom Hearts, Square Enix wowed fans with a trailer for several different Kingdom Hearts projects including Kingdom Hearts 4. Notably, Sora appears in Quadratum and battles a titanic Heartless in the middle of a bustling city. So, just what is Quadratum?
Quadratum was introduced in Kingdom Hearts 3 and is also known as Shibuya. Ansem the Wise describes the world of Quadratum as unlike any other in the Kingdom Hearts universe as it is "not a world of light or dark, but a world of fiction that exists on the other side."
The story and lore surrounding Kingdom Hearts are enough to make even the most dedicated fan's head spin. The long and short of it is that Quadratum is based on the real world, our world. Aside from Kingdom Hearts 3, it was also mentioned in Kingdom Hearts Melody of Memory as the place where Riku dreams about and in Kingdom Hearts 3D: Dream Drop Distance as the place where Neku Sakuraba, Joshua, Daisukenojo Bito, Rhyme, and Shiki all originate from. It's an important world that appears to be finally getting its due.
For more Kingdom Hearts goodies, check out Kingdom Hearts Traverse Town Walkthrough – KH 1.5 on Pro Game Guides.