A very repetitive game
The Multiplayer is the same as the story but with someone else from Xbox Live. And there is an achievement you can get by playing Multiplayer.
The achievements are actually challenging in this game. Most of them are beating each level without dying, and there are some of the easier ones where all you have to do is beat the level.
So I would say if you know someone who has this on their Xbox play it, but I don't know about buying it.