You control a 'circle of antimatter' into which the
bouncing aliens, who inhabit this planet, are sucked. But if
the vortex you control is slightly off-centre then the vortex
itself is itself destroyed.
If you cannot clear the area of bouncing beings before the
stars twinkle their last then your time (and game) is gone.
The first two sheets are easy enough, with few and fairly
slow bouncers to hoover into your antimatter, but on the
third the bouncers bounce off the sky, needing fast thinking
and mental geometry unless you are prepared to turn the VDU
upside down!
Unfortunately, that's it - there are no extra revelations
as you move through the game.