The Kingdom Hearts series has always been about exploring the intersections of various worlds and blending characters together, but the reveal of Kingdom Hearts 4's Quadratum has caused speculation about how these possibilities could expand in the future of the franchise. Previous titles have maintained a look between cartoon and anime even while crossing over with live-action properties, but Kingdom Hearts 4 is taking a further step into realism with its hub world. With a cityscape resembling the real-life location of Tokyo's Shibuya, one fan-favorite character's once-unlikely return has started to seem increasingly plausible.