The biggest difference between this game and the first, is that the first is a very happy game, whereas this one can be a lot darker at times. I mean, I've already mentioned that Bottles is killed right at the start (though his ghost hangs around), one side-quest involves you having to KILL two innocent non-playable characters (and this has to be done if you want 100%!), you meet a perfectly nice happy person who is shortly afterwards transformed into a zombie which tries to attack you, you find the ruins of a house and read about how the whole family was killed when their home was destroyed, and lots of other things like that! None of it is taken too seriously though. It's also a lot aesthetically different too, there aren't as many colourful 'happy' worlds anymore: now you're going through places like an enormous toxic factory, an abandoned amusement park or an old mine.
The different places to visit are one of the biggest changes between this game and its prequel. Whereas in the first game you go through Grunty's castle and find doorways which are basically portals to completely unconnected areas, the Isle of Hags feels like one big world, rather than lots of smaller worlds connected by a hub. In this game, you might meet somebody in one world, and then do something for them which then prompts them to go somewhere else and then you'll later find them in a different world. There're even physical connections between the worlds (such as going down a corridor in one world, leads to another) and even a train service between them!
Gameplay-wise, though, things are mostly unchanged from the first game, the only difference being that you slowly learn additional moves not seen in the first as the game goes along. You can also occasionally play as Mumbo now, which adds some nice, but minor (since he can't do much), variety. One interesting thing, though, is that there are now first person shooter style areas. There aren't many of them but there inclusion brings a fresh new way of playing to the game, and there's even a very fun multiplayer shooting mode (and also several mini-games you can do on multiplayer, which are quite nice too).
Rating: 9.8/10 (just as good as the fist, but for different reasons)
(I do not own the copyright of the screen capture.)