Liberator

Atari Force Liberator is an arcade game based on the Atari Force comic book series. Atari Force was published by DC Comics from 1982 to 1986. The story Atari Force Code Name: Liberator describes the premise of the arcade game in detail and was included as part of Superman in the House of Mystery issue #53, published in 1983. Characters and concepts from the comic exist throughout the game. In the opening screen of the arcade game, Commander Champion of the Atari Force asks you to help free the galaxy from the evil Malaglon Army. Commander Champion of the Atari Force has chosen you as the Liberator.

Liberator is commonly described as the opposite of Missile Command. The objective of Missile Command is to defend your bases from a space-based attack. Liberator's objective is the exact opposite, destroy enemy bases as you orbit their planet. Liberator was released by Atari in 1982. The arcade game was not very popular and only 762 arcade machines were ever made.

Gameplay
The Liberator controls consist of a trackball, fire button, and shield button. The player controls a coordinated attack from four star ships at the corners of the screen. The primary target of the attack are enemy bases on a rotating planet in the center of the screen. The trackball is used to move a cross-shaped cursor. The fire button fires a missile at the cursor's location from your closest ship. The shield button is used to activate force fields around the ships. The shield can only take four hits each round, and the count is shared between all ships.

At the beginning of each level, the player is flying through outer space and spaceships fly on screen from the left and right and leave in an arc. They try to ram into your ships. Note that shields do not work during this stage.

After this stage, the player is taken to a view of a rotating planet. The most prominent enemies are red flashing missile bases. They shoot missiles, fireballs, and star balls at your ships. The enemy bases can also detach from the planet, turn into satellites, and orbit the planet while shooting missiles. Once all missile bases are destroyed, the player moves onto the next level. At higher levels, there is the white master base. It is very intelligent, and it can change the direction or speed of the planet rotation to avoid getting hit.

Other important facts:
 * Missiles can be destroyed, although some split into four smaller particles when destroyed.
 * Fireballs take four hits to destroy, but they slow down on each hit.
 * Star balls take four hits to destroy, much like fireballs. However, unlike fireballs, they return to normal speed soon after being hit.
 * Flying saucers will sometimes appear from the planet. flying saucers shoot a large, deadly laser which cannot be stopped.
 * Bonus ships are earned at 20,000, but they are not applied immediately. Instead, they are added only after each stage.
 * After inserting coins, if the player holds the fire button then presses the start button, he will be taken to a level select, allowing him to start at any third level (1, 4, 7... up to 22).

Ports
Liberator was ported to Microsoft Windows, Xbox, and PlayStation 2 in 2003 as part of Atari Anthology, a collection of Atari arcade and 2600 games. The game was made available on Microsoft's Game Room service for its Xbox 360 console and for Windows-based PCs in June 2010.