Atlantis is a fixed shooter game released by Imagic in July 1982, for the Atari 2600. It was written by Dennis Koble who also wrote Trick Shot, Solar Storm, and Shootin' Gallery for Imagic. Atlantis was ported to several other systems including the Atari 8-bit computers, VIC-20 and Intellivision. The Magnavox Odyssey² received its port in 1983. The game was inspired by Taito's 1981 Colony 7 arcade game.
Atlantis was the subject of Destination Atlantis, a competition held by Imagic in 1982. Imagic invited players of Atlantis to take pictures of their high scores on their television screens and mail them to the company. Those who had the highest scores were then rewarded with a copy of Atlantis II. The latter game, rather than being a mass-produced sequel to Atlantis, was a special edition of the original featuring faster enemy ships which were worth fewer points. The concept behind this was to create a more difficult game that would "determine the true champion". As very few cartridges were created, Atlantis II is now a rare and highly-valued collectors item.
In the game the player controls the last defenses of the City of Atlantis against the Gorgon invaders. The city has seven bases, which are vulnerable to attack. Three of these have firepower capabilities to destroy the Gorgon ships before they manage to fire death rays at one of the settlements. The gun bases have fixed cannons; the center base fires straight up, while the far left and far right bases fire diagonally upwards across the screen. The center cannon also creates a shield that protects the settlements from the death rays, so once the center cannon is destroyed, the remaining settlements become vulnerable to attack. The enemy ships pass back and forth from left to right four times before they enter firing range, giving an ample opportunity to blow them away. Lost bases can be regained by destroying enough Gorgon ships.
Regardless of the player's efforts to avert the tragedy, Atlantis is doomed. The only way the game can end is when all bases are destroyed. However, a tiny ship then rises from the rubble and speeds away, making a connection with another Imagic game, Cosmic Ark.