Crazy Machines 2 is the "real" sequel to Crazy Machines (after the stand-alone add-on Crazy Machines 1.5). The series got a complete overhaul and features now improved graphics and sound.
While the concept of the series has not changed since its first incarnation (and its spiritual ancestor The Incredible Machine), the game has now grown to over 150 different objects and over 200 pre-designed "head-scratching" puzzles.
The main feature of the game is a so-called "extraordinary journey around the world". Which is basically a very long line (150) of different experiments. The "World Tour" is divided into 15 levels with 10 stages each. Naturally a "Beginner's Lab" is included for starters. To ease the pain for all those, that a not gifted with supreme knowledge of physics, the game offers varied support. Also the player doesn't have to clear every puzzle to advance on the "world tour", seven out of ten is sufficient.
Additionally the AGEIA PhysX engine to emulate dynamic and unscripted physics for more realistic challenges has been implemented. The addition of the AGEIA PhysX engine lead to the inclusion of a section, which you can only play, if you have AGEIA hardware.