The object of Tempest is to survive as long as possible and score as many points as possible by clearing the screen of enemies that have landed on the playing field. The game takes place in a closed tube or open field which is viewed from one end and is divided into a dozen or more segments. The player controls a claw-shaped spaceship that crawls along the near edge of the playfield, moving from segment to segment. This ship can rapid-fire shots down the tube, destroying any enemies within the same segment, and is also equipped with a Superzapper, which destroys all enemies currently on the playfield once per level. (A second use of the Superzapper in a level destroys one random enemy.)
Enemies swirl around at the far end of the playfield, then enter the playfield and move toward the player. When all enemies in a level are destroyed or reach the near end of the playfield, the player "warps" to the next level by traveling down the playfield. The player must avoid or shoot down any spikes left behind while warping. The player loses a ship when an enemy comes into contact with their ship, shoots it or otherwise destroys it, or if the ship hits a spike while warping. If an adequate point threshold is reached, the player can earn a new ship. The game is over when the enemies destroy all of the player's ships.
The game consists of sixteen screens with unique geometric shapes, some of which are closed tubes that allow the player to loop around, while others are open fields that have distinct left and right endpoints. When all sixteen screens have been played, the sequence repeats with a different color scheme and a higher difficulty level, including the invisible (black) levels (65–80). Each sequence of levels adds additional enemies that are faster and more deadly to the player's ship. The numbered levels stop incrementing after level 99 and a random one of the 16 variations will appear after successful completion of subsequent levels.
Tempest introduced several new features for its time. It was one of the first video games to use Atari's Color-QuadraScan vector display technology (along with Space Duel, which was released around the same time). It was also the first game to allow the player to choose their starting level (a system Atari dubbed "SkillStep"). This feature would increase the maximum starting level depending on the player's performance in the previous game, essentially allowing the player to continue, a feature that became a standard in later video games. Finally, Tempest was one of the first video games to sport a progressive level design in which the levels themselves varied rather than giving the player the same level with increasing difficulty levels.
The game was initially meant to be a 3D remake of Space Invaders, but such early versions had many problems, so a new design was used. Theurer says that the design came from a dream where monsters crawled out of a hole in the ground.
Three different cabinet designs exist for Tempest. The most common cabinet is an upright cabinet in the shape of a right triangle sitting on top of a rectangle, when viewed from the side. This cabinet sported colorful side art. A shorter and less flashy cabaret-style cabinet was also released with optional side art, and a cocktail-style table cabinet allowed two players to play at opposite ends of the table. In this configuration, the screen would flip vertically for each player."
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