Caverns of Mars is a computer game originally made for the Atari 8-bit computers, programmed by Greg Christensen and published by Atari Program Exchange (APX) in 1981. It became the best selling APX title of all time, eventually being released by Atari in game cartridge format. The game was developed to a prototype stage for the Atari 2600, but wasn't released on the console. Said prototype would show up as one of the games present on the Atari Flashback 2, a plug-and-play 2600-style device containing 42 built-in games and from there found its way into Homebrew release for the 2600.
Martian galactic fleets surround the planet and are demanding its surrender! The Terra IV High Command knows that your space fighter, the HELICON VII, is he only craft equipped to invade the Martian Headquarters deep within the Caverns of Mars. Your mission: Sabotage the Martian defense system by activating their deadly fusion bomb.
Make your way down two to five caverns, depending on the difficulty level. Do not hit the walls of the cavern or any Martian items. You will need to shoot fuel tanks as you go because you use fuel constantly. You must make your way through all the caverns to the fusion bomb, which you then touch to activate. Once activated, you must return to the surface before the bomb explodes.