An obscure, coin-devouring attempt at evolving the saturated shoot-'em-up market of the early '80s, Gravitar is perhaps best described as Asteroids covered in oil with a big weight around its neck. Only in a good way.
Trolling out the short lived colour vector technology Atari was investing in so heavily, every gamer's first few coins were lost to the opening screen which featured the ship materialising in the midst of an alien infested solar system. Like all good stellar nurseries, at the centre is a sun with massive gravitational force. The first thing players noticed was their small, arrow-shaped fighter being sucked into the star's corona and immediately flash fried. But for those few who sacrificed another credit, it was uphill from that point on.
As the unambiguous name suggests, the real enemy of Gravitar is gravity. When cruising the solar system looking for planets to destroy, the ship is dragged toward the sun (while avoiding the flying saucer previously seen in Asteroids), but once on the planet's surface and faced with the task of blowing up the many gun turrets, the ground becomes the source of gravitational constant. These planets are in all shapes and sizes (one of Gravitar's more unique and intriguing features) from roughly spherical planetoid's to horizontal landscapes and open caves.