140 is a minimalistic rhythm platformer. The basic idea is that the game mechanics are tied to the music. So, if a platform moves, it will move on the beat. That gives it a very intuitive feel. At the end of a level, there's also a boss fight, which is an interesting digression from the main game. The bosses keep to the tempo and all feel very unique.
The game also has frequent checkpoints, so it's no big deal when you die. Unless you're playing in the hardcore mode where things go right to left rather than left to right and there are no checkpoints. That's a different game entirely.
Overall, not playing the hardcore mode, the game was only about an hour, but aside from the shortness, the game was great!