A solid sequel that changes things up in a lot of different ways. For a start, levels are now arranged into a world map, which allows for some forks in the road, optional levels, and so forth. Levels also have multiple variants as well, giving the game longer legs. In addition to a nice slate of new mechanics that are fun to mess with, the game also adds terrain and water, which expands the scope of what sort of puzzles can be built. It's a solid sequel that does a lot to keep things fresh.