From the inlay (Soft Aid Compilation):
The Pyramid contains 120 chambers on 15 levels. In order to get from one chamber to another you must fight off the indigenous aliens to collect an energised crystal which will neutralize the force field guarding the two exits. The Pyramid is inhabited by a total of 60 weird and exotic alien types. Apart from going for a high score the Pyramid contains a number puzzle to solve, the more chambers successfully visited, the more information is gathered to enable you to solve the puzzle of the Pyramid.
In The Pyramid, the user starts exploring from a top of a great Pyramid. Each block rest upon two others. Within each block, the user controls a spaceman which can fly up, down, left or right. Enemies fall from the ceiling or rise from the floor and they must be either avoided or shot until a diamond appears. This opens two exits at the bottom of the level which lead either to the lower left or right block. The player therefore navigates down the Pyramid, but every game is slightly different if they make different selections.