At the main menu, select "Start Game." Next at the "Enter your initials" screen press Down, Down, Down, Down, Right, Down, Down, Down, Down, Right, Down, Down, Down, Down, A. Then select "Start Game" again. You'll now be able to select any level by pressing Right or Left at the following screen.
First enter the previous code for Stage Skip. At the level select screen, elect "Exit", then select "Game Options". Next select "Done". A new options menu called "Secret Garden" will appear.
Enter the gopher symbols as your name to unlock an extra menu at the options screen.
When on the first level, make your way to the boss, but instead of flying to him go up and right you should find a health generator. Shoot at it and and a energy icon will appear. Take it and you will be rewarded with a 1000 points and a lot of energy.
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