This but the donut is 4d so that 3d things can move around on it (I think...)

I asked ChatGPT to explain it to me and it came up with this:

This description is discussing a theoretical concept where the universe is shaped like a donut, known as a "3-roid" or "3-tauroid". In this model, moving through the universe is akin to navigating a 3D surface of a 4D object, similar to how a spaceship in a 2D video game wraps around when reaching the edge of the screen. The suggestion of characters with 4D movement abilities falling out of space and time is a speculative idea based on this theoretical framework.