Complete all 13 bonus levels destroying all spheres. This needs to be completed with one game so start at Stage 1 Level 1 on Easy and work through to the end of Stage 13-5. The game may be saved but you must continue each time. If you lose all your lives, you will need to restart at Stage 1 Level 1 to unlock this achievement. Even though Stage 12 and 13 get challenging you should be able to complete it fairly easily. Collecting coins during the easy stages will see you finish with around 20 lives.