Renan Ferraz, also known by his alias "Fantasma," is a notorious Brazilian serial killer and torturer. His criminal history is marked by numerous home invasions, mutilations, dismemberments, and acts of torture. Before his involvement with the ISG and other groups, Ferraz was diagnosed with antisocial, schizoid, and loner personality traits. He was also noted for being unhygienic and a virgin, which further isolated him from societal norms. Ferraz drew significant inspiration from other infamous killers, including Caio Henrique, Adriano Silva, Nathan Vieira, and Richard Chase. These individuals likely influenced his methods and the psychological aspects of his crimes.