Andrei Chikatilo (The Butcher)
This guy is definitely a psycho especially with how he justified the murders he has committed. According to investigations, he has killed, assaulted and raped over 50 women in Russia from 1978 to 1990. Just two years after he was captured in 1992, he was ordered to be killed via firing squad. According to him, he always brings a knife because it brought him psychological relief. He also said that he was a mistake of nature and has to be destroyed.
