An action light novel about Black Ranger - a superhero who turned into a hero slayer. Something was going through the Black Ranger's mind, he willingly distanced himself from the good reputation as a superhero and turned into a villain. He killed his opponents brutally, even other superheroes became his victims. Since then, he always called himself KILLER RANGER, a figure who would eliminate either friends or foes. What is the motive behind such a massive change? Killer Ranger is written in the Indonesian language only, for now.