OverviewClash at Demonhead (known in Japan as Dengeki Big Bang!) is an open-ended action platformer developed and published by Vic Tokai for the Nintendo Entertainment System in January 1990. The game features non-linear exploration (similar to the Metroidvania gameplay concept), in which players choose their route at many points throughout the game.
StoryThe player takes the role of Billy "Big Bang" Blitz, a sergeant in the Special Assault Brigade for Real Emergencies, or S.A.B.R.E. He and his fellow operative Mary have been tasked with the rescue of Professor Plum, a genius who has crafted the doomsday bomb, a weapon capable of destroying the entire world. Bang sets off on his journey, eventually encountering Tom Guycott, the one who plotted the kidnapping. Billy learns that the Doomsday Bomb is controlled by six medallions, which have been scattered around the world, and are being held by the governors of Demonhead,. While retrieving one of these medallions, Billy meets a hermit who helps Billy by teaching him a number of special force powers. During his quest to retrieve the medallions; Billy also experiences mysterious mental problems.
Later on in his journey, Big Bang discovers that these mental discomforts were actually attempts to control his mind by a demon underneath the mountain in the north of Demonhead. The demon is eventually able to take control of one of Billy's allies, Michael, but he is released. The demon kills Tom Guycott, and steals the medallion he possesses. The hermit who assisted Billy earlier tells Billy that this demon can only be destroyed with the Sword of Apollo. Billy obtains it, defeats the demon, takes Guycott's medallion, and attempts to rescue professor . Unfortunately, the Doomsday Bomb has already been completed. As it turns out, Plum wasn't behind the bomb at all, it was actually created by aliens who created humankind 1,000 years ago, and now having grown disappointed with their creations, decided to bring the world to and end. Luckily, Billy diffuses their attempt with the medallions.