The levels are nonlinear, and focus on puzzle-solving and dexterity rather than speed (though the levels are timed, and you can track your times for each level). One unique aspect of the levels is the ability to interact with the background. Most levels consist of two layers - a front area and a back area - that you can periodically move between. When you are in the front area, enemies and switches can be seen in the back area, forewarning you about the next part of the level. If you have access to a cosmo ball (a red ball that Blender can throw to kill enemies or hit switches), you can throw it upward to hit objects in the back area, allowing you to eliminate enemies before having to cross paths with them.