Spectral Invaders

Earth is under attack from fleets of alien space ships. Conveniently lined up
in nice grids, the aliens sweep side to side, dropping one row each time they
reach the edge of the screen. Avoiding their bombs, the player has a tank that
can trundle left and right at the bottom of the screen, hiding behind
gradually crumbling buildings for cover, and has to shoot the aliens before
they can land. Yes, that’s right, it’s a version of Space Invaders for the
Spectrum.

Spectral Invaders