From Wikipedia.. Mad Insanity is Mars & J RZ J RZ is Mars's homeboy Mars (Born Mario Delgado[3] in 1980) is an American rapper from the San Francisco Bay Area.[3][4] In 2005, he received national attention when fan Jeff Weise frequented Mars' website and forum before killing nine people.[5] In 2009, Mars received attention when it was learned that Mars' music was an influence on the music of horrorcore fan Richard Sam McCroskey, who allegedly killed four people.