The virus

You are located in the rooms of Prof. Bergmann, who once researched new combat agents on behalf of several states. Under his direction, some of the most renowned combat substance researchers worked - until Day X, when Professor Bergmann burned half of his face. He has never been seen in public since. Children tell stories of an evil figure at the slaughterhouse in Düsseldorf Derendorf. But what does all this have to do with the disappearance of several teenagers in Düsseldorf?