Here are some cheats and tips for the game Zapper.
Unlimited lives:
Pause game play, then hold L and press Up (3),
Left (2), Right, Left, Right.
Unlimited shield:
Pause the game, then hold L and press Up, Down,
Up, Left, Right, Down, Up.
Cheats:
Collect all 400 fireflies in a level to unlock
the corresponding cheat.
Level 1: Insect Eye. Changes your vision.
Level 2: Screen Switch. Reverses level.
Level 3. Auto-Hop. Hold D-pad to keep Zapper moving.
Level 4: Infinite Super Zap. Zapper always has a Super Zap.