Cheat mode:
Enter one of the following high score names to enable the corresponding cheat function. REMEMBER: The codes will remain active until the cartridge memory is cleared.

Plazma Pong
Enter NOLAN as a high score name. The word "Perfect" will be spoken to confirm correct code entry. A "Plazma Pong" option can now be selected as a game option.

Flossie Defender
Enter OVINE as a high score name. The sound of a sheep will confirm correct code entry. Press any button to select a "Defender Plus" game, then press A to start.

Level skip
Enter BEEST as a high score name. The sound of a sheep will confirm correct code entry. Begin a Defender 2000 game and press 3 while playing the game to jump to the next level. Press 6 while playing the game to access the warp screen.

Extra bonus:
Retrieve a falling human as a wave ends.