Demolator

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

Following the Thousand Year War with the Alien Demolators, the last remnants of the human race are being transported across the galaxy in cryogenic stasis aboard the B.S. Quinn. However, the Demolators have invaded the cargo bay, and it is the player's job to destroy the Demolators and protect the human cargo.

The player controls the robot Xeno, directing its movements on two planes and firing an ultrasonic cannon to defend the remaining humans. Enemy Demolators race horizontally across the screen and pass over top of human cargo. Initially every seventh cargo they pass over is destroyed, and each level has an additional Demolator up to eight per level, and then this reduces to four, but they then destroy every sixth human cargo. Minors appear stationary on the screen, and later morph into mines than can not be removed. Protectors move about the screen and fire towards the player. Finally, the Trackor homes in on the player's position, and fires towards the player. The player clears a stage when all Demolators are destroyed, but destroyed humans persist between stages.