The Death Ray was a ray gun designed to kill people, using short red laser-beam blasts; it was presumabl) powered by Wonderflonium. Dr. Horrible eventually created one out of of a modified Stun Ray, in an event which marked the beginning of his descent into evil. Dr. Horrible fired it several times successfuly in the air to frighten his audience at the unveiling of a statue of Captain Hammer. It was forcibly taken from Horrible by Captian Hammer who turned it on him. For some reason, however, when Hammer tried to kill Horrible with it, it misfired, instantly exploding into pieces.