There's something about the way that you can hold "z" while you're off the level to make a second person appear that reminds me of that christian copypasta about the guy looking back on his life as a set of footprints in the sand (http://www.marypages.com/footprints.htm). I find something really compelling about the idea of this shadow person who walks with you when you're in this liminal space, who only appears when you press a button that otherwise doesn't do anything. I also like the few unmarked tiles in the middle of the world. I've wondered about trying to use non-buffer-cleared space as part of the composition of the world, it's interesting to see it at work here.