Arrows: move "left"/"right"/forward/backward A/D: turn "left"/"right" (rotate in XW plane) W/S: turn up/down (rotate in YW plane) Q/E: turn "left-2"/"right-2" (rotate in ZW plane)
TurboWarp: https://turbowarp.org/919666650 This one's a bit difficult to explain, but I'll give it a go: Imagine being inside a 3D cube. You see a front face (square) in the +Z direction (just a convention, let's roll with it), four side faces (they look like trapeziums from your perspective, but they're square) in the -X, +X, -Y and +Y directions, and you know there's a back face in the -Z direction. In total, there are 6 faces. Being inside a 4D tesseract is similar. 4D space has 4 coordinates - X, Y, Z and W - so you see a front "face" (a *cubical* cell) in let's say the +W direction, but now there are *six* cells to your side; -X, +X, -Y, +Y, as well as -Z and +Z. And there's a cell behind you in the -W direction. In total, there are are *8* cells. This is like that, except instead of a cube, there are bouncing balls to keep you company.