Much better game than ratings indicate
The game also has a good mix of achievements. A couple of classic collection achievements, the standard completion achievements (both level and game), as well as the attack/performance achievements add some variety to the game.
My only complaint is the lack of achievements for a second player in co-op mode. I was playing with someone else at first; however, I got the achievements for various missions, while he did not. At least it tells you that upfront (prior to playing).
If you are looking for a good game to pick up for achievements or just for a good themed game, the now $20 price tag is worth the cost. If you have yet to play this game, it is much better than the critics gave it.