First, I thoroughly enjoyed the game. It's amazing how something so simple on the surface can be so much fun But, in playing it, I found myself wondering about terrain engine of sorts he used. Does he just draw a 3 dimensional array of cubes, say around 1000x1000x128? Or do you think he uses some sort of raycasting to only draw the visible ones? I find the idea of a terrain that isn't just a heightmap to be neat, even a fairly "low resolution" on built up of cubes. Any thoughts how this could be implemented in Unity?