Defender is an arcade video game developed and released by Williams Electronics in February 1981, and Revenge of Defender is an Amiga game based on original Defender by Epyx at 1989.
A horizontally scrolling shoot ’em up, the game is set on a fictional planet where the player must defeat waves of invading aliens while protecting astronauts. Development was led by Eugene Jarvis, a pinball programmer at Williams; Defender was Jarvis’ first video game project and drew inspiration from Space Invaders and Asteroids.
Press [Space] during game play to display the options screen. Highlight the “View Game Screen” option, then press Left + Fire on the Joystick. The game screen will appear. Release the joystick and press Fire. The option screen will reappear. Highlight the “Sound On/Off” option, then press Right + Fire on the Joystick. Highlight the “View Game Screen” option again, then hold Right on the Joystick, hold the Right Mouse Button, and press the Left Mouse Button. The option screen should display “Cheat Mode” to confirm correct code entry. Resume game play and press Fire for unlimited shields. Any level can be selected from the options menu.