Mutant Invaders

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

The player controls a small ship that moves horizontally at the bottom of the screen and fires vertically. The player can also hyperspace to a random place at the bottom of the screen if surrounded by danger. The player cannot move or fire while a previously fired energy beam remains on the screen.

Alien refueling bases traverse the top of the screen, and can be shot for bonus points. Alien vessels have the ability to temporarily phase into hyperspace where they cannot be shot. Red mutant invaders cannot be destroyed, and will sit at the bottom of the screen endangering the player. They can be removed by luring a green invader into their position.

Every 500 points, all invaders turn to mutant invaders, one of which is real and the others are fake. The real mutant must be destroyed to clear the enemies. This pattern repeats, and at 1,000 points, the invaders return to green with two mutants present. The player starts with three lives.