There are two different reviews I want to write. One is what I would give the game if I only had to look at it, and the other is what I give the game when I played it.
To begin with, the game is drop-dead-gorgeous. The UbiArt Framework shines in the game. It runs at a great pace, and the effects are just great. The animations too are wonderful (but that's a bit of a problem as I'll explain in a bit.) There is an overwhelming amount of content. It's definitely worth a rent.
Now, the problems. To begin with, the Murfy levels are just awful. Globox doesn't do what you want him to do half the time--especially when you get to the later levels. In one, you have to use a shield to protect him from fire. However, if you don't drag the shield as far as his AI wants, he just stands there. It took me several minutes to drag it the microscopic difference necessary to trigger him to move forward.
The next issue is that I feel like the developers just couldn't say no to any idea they had. Turn Rayman into a chicken? Yes please.....but only for 30 seconds, then we'll forget the idea completely and go on to something else. It's manic. (And not always in a good way!) They don't give any of the ideas any time to breathe. It's one new thing after another.
Then there are issues with the beautiful animation impacting gameplay. It is possible to get hit two times in rapid succession by the same enemy and die immediately. Take one of the boss battles. While Rayman was going through his damage animation, he wasn't able to move...thus causing him to die immediately. After dying, the game reset to the beginning of the battle...only for me to die instantly, because I didn't anticipate that it wanted me to randomly jump. There's a randomness about the difficulty that's just....strange. It goes from super easy to "I'm going to throw the controller" in a matter of seconds.
I recommend the game, overall. I don't think it's the modern classic many are making it out to be though