Space Cavern is one of a multitude of ho-hum games for the Atari 2600. Released in 1982 by Apollo, it was released into a glut of similarly average to below average games that were largely responsible for the video game crash of that era. Space Cavern received mostly mixed to negative reviews and doesn't really stand out from the pack. Like many games released during this time, the box art is arguably better than the game.
Space Cavern was one of ten games released by Apollo in about a two year time span. Space Cavern was also released as Space Canyon by Panda the following year. This version seems to be pretty rare and I have no idea what the story is behind Panda or why they could also publish this game.
Space Cavern is fairly typical of fixed vertical shooters of the era. The one somewhat unique twist was that in addition to enemies coming from above, they could also come after you on the ground from the left or right. Since the Atari 2600 joystick only had one button, you had to press up or down to fire left or right while the fire button fired up.
As far as I know this game has never had a re-release but you aren't missing much. The cart can be had pretty cheap if you really want it or you can check it out on an emulator. For better games of this genre check out Space Invaders, Gorf, Galaxian, Galaga, etc.
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