Fun game.
That was an interesting, original, and fun concept. I found it very challenging but fun nonetheless. When I was invisible, I would sometimes think I was going in the right direction, but then I would die on the opposite end of the level and think: "How the hell did I end up there?" Great game. I couldn't find the hidden medal but I have some guesses as to where it could be. Also, I noticed a faint outline of my person appear as I narrowly avoided electricity.