It's like all three Rayman games rolled into one!
Long before I bought the game I absolutely fell in love with the vibrant, painterly graphics. When I did, I was really impressed with the smooth character animations and scrolling as well. It's so graphically beautiful I don't have much else to say about it apart from that. Most of the sound is imported and translated from the Nintendo 64 version of Rayman 2, apart from what sounds like a few new sounds for the Hoodlums and Murfy. I think the music translates very well for Gameboy advance, as do some of the sounds.
Now, being a 2D side scrolling game, the gameplay is very relative to Rayman 1. You run, throw your fist to shoot, swing on floating hoops, climb, fly with the helicopter hair - yep, it's all there, along with relative elements of Rayman 2 such as vine climbing and climbing between two walls. And much like Rayman 1, the game gets progressively harder. To give the feel of Rayman 3, you get to fight some of the Hoodlums as enemies, and they have their own hideout as a map, while every other map is Rayman 2 based. There might not be much more to this than the side scrolling Rayman 1 like gameplay, but this game really is worth picking up. In my case, I traded some of my least favourite PSOne games in my collection for this, meaning that it's worth having more than all those games put together.