I've played this game at PAX East five years ago. Loved it then, still want to play it now. The tutorial does a remarkably good job of teaching you the basics, but think of it like this. You have four dimensions, height, width, depth and the fourth one. Basically with a button press you replace depth with the fourth one. So you can wander around in four dimensions. It's really hard to describe better than that, but it's worth playing once it finally comes out.