Liberator

Liberator is a 1-player arcade game for the BBC Micro.

Following an attack on the player's planetoid by mutant raiders, it is discovered that several hostages have been taken. Flying in a warp-ship, it is the player's duty to return the kidnapped citizens.

Played from a first-person perspective, the player moves a crosshair on the screen to shoot mutant power pyramids. In the first three stages, the player flies through flat plains, a mountain tunnel, and then a defended valley. Triangles and enemy creatures appear on the horizon. White and red ones can be shot for increased energy, but the player loses energy if they fail to shoot a red enemy. At the end of the third stage, the remaining energy can be used to save hostages. The player moves their ship left and right from a top down perspective in the fourth stage, and must avoid red triangles that approach from the bottom of the screen. When a hostage appears, the player can use their transport beam to rescue them.

After completing a hostage rescue mission, the player attempts the challenge again with more dangerous mutants.