A retro-ish based game on some old classics. In the preceding millennia ancient civilisations predicted the return of a large celestial body in our Solar System with a highly elliptical orbit so far away that it could take it 15,000 years to orbit the Sun. It has returned, knocking comets out of their orbit in the Kuiper belt, some heading for Earth. As part of the planetary defence expedition it is your role to protect Earth from these comets. Good luck . . .