The beauty, brilliance and joy of this game is its subtlety. It slowly unnerves and saddens the player an challenges them just enough to make sure they're focusing on the experience. Using this it gently places you within the confines of this world and when the ending rolls around its that much more effective.
Only a 4.5/5 because its a one or two time experience and after a few play-throughs its less effective emotionally. Still an incredible and simple art game.