While Castlevania was being developed for the Nintendo Entertainment System, Konami was also working on a similar title for the MSX2 home computer. The game was called Vampire Killer and released on October 30, 1986.
While it did share many similarities with Castlevania, in Japan it even has the same name, the game differed in many other ways and is generally more open-ended. Players had to find keys, for example, and the game contained hidden merchants that would sell them useful equipment.
Nintendo’s Japanese website now includes a page for the game that specifically mentions that it’s the MSX version. Will we see a port of the game in Europe or North America? Unlikely. As Joystiq points out in their article, the online storefronts in western countries don’t list games for the MSX system.
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