Innovative and memorable
Now, there's a lot of bad reviews for this game, mostly concerning it's short length and lack of replay value. Although both arguments are true, they ignore the strongest, and only, reason you need to get this game: it allows you to experience an innovative and totally unexpected gameplay. Every level presents a new and creative challenge. If replay value was a deciding factor, all puzzle games, even Shadow of the Colossus, would have to be terrible because there's no urge to replay it once you've solved the puzzles.
I strongly recommend this game to everyone. You won't spend a lot of time playing it, but you'll definitely enjoy and remember this game.