Ghostbusters
Ghostbusters was published by Sega and developed by Compile for the Mega Drive/Genesis on June 29, 1990. It has nothing to do with the earlier Activision game (although its name still appears in the copyright screen) and is instead a 'run and gun' game in which the player takes control of three of the four Ghostbusters from the movie, with the conspicuous absence of Winston Zeddemore. There are four levels to start with, after completing which a fifth level is unlocked, followed by a sixth and final level. In each level, there are a certain number (usually two) of intermediate bosses known as "middle ghosts". After a medium ghost is defeated, it turns into a small green ghost that can be caught for extra money by luring it over a ghost trap. Between levels, you can use the money to buy power-ups, such as a 3-way shot or recovery items.
Story
The ghost hunters are stymied by a lack of ghost activity when suddenly several calls come in from all over town, including the reappearance of the Stay Puft Marshmallow Man (although the dialog indicates it's not the same one from the movie). After each case, a piece of a stone tablet is collected. The three ghost hunters put the mysterious tablet together, inadvertently opening a portal to the "evil world" and freeing a horde of ghosts. In the end, however, the ghost hunters manage to defeat Janna, the god of darkness, and retrieve a mystical gemstone from the evil world. They combine the gemstone with the tablet to close the portal and save the city.