Bonus Levels
Bonus Level 13: Collect all the dinosaur fossils in levels 1-12
Bonus Level 14: Collect all the dinosaur fossils in levels 1-12
Bonus Level 15: Collect all the dinosaur fossils in levels 1-14

Enable HARD Mode
     Enable HARD Mode (faster & more enemies, etc.): Beat levels 1-12.

Sound test option
     Drown the monster in level 12 to unlock the sound test option.