One or two players control space fighters assigned to deal with an alien invasion using incredible firepower through eight stages.

In the future, Earth has achieved a state of global peace, but one problem has arisen: a wholesale disappearance of young women.

Unable to mate with their own kind, the people of Zancs have found the perfect reproductive substitutes in the women of Earth, abducting them to keep the planetary population steady.

The music during the demo of the game includes Fantaisie-Impromptu by Frédéric Chopin, and the ending theme contains the fourth movement of Beethoven's Symphony No.

In Japan, Game Machine listed Megablast on their December 15, 1989 issue as being the twenty-first most-successful table arcade unit of the month.