The making of a serial killer is quite different from an average man, as is understood from the words of an American serial killer Ted Bundy, who assaulted and murdered numerous young women and girls during the 1970s.

"I'm as cold a motherf*cker as you've ever put your f*cking eyes on. I don't give a sh*t about those people," Pshychology Today quoted him.

Here are some of the most notorious and unforgivably cruel serial killers of all time.

Gilles de Rais

Gillesderais
GillesderaisCreative Commons/Éloi Firmin Féron

Gilles de Rais, a 15th century nobleman, considered to be the precursor to the modern serial killers, used to be soldier alongside Joan of Arc and was one of the wealthiest men in France. Crime Library chronicles that Gilles hid a dark and sinister side for many years, during which he kidnapped, tortured and murdered hundreds of peasant children (mostly blond-haired, blue-eyed young boys). Eventhough the precise number is unknown, it is generally placed between 80 and 200.

In a transcript of his trial, one of Gilles' servants Henriet described the actions of his master: "He experienced intense pleasure in seeing them in their agonies," Muldersworld uncovered. "But his great passion was to welter in their blood. His servants would stab a child in the jugular vein, and let the blood squirt over him... When the horrible deed was done, and the child was dead, the marshal would be filled with grief for what he had done, and would toss weeping and praying on a bed..whilst his servants washed the floor, and burned in the huge fireplace the bodies of the murdered children... An insupportable odour filled the room, but the Maréchal do Retz inhaled it with delight."

Vampire of Sacramento

Richard Trenton Chase, who was known as the 'Vampire of Sacramento' due to his habit of drinking victims' blood and cannibalism, was an American schizophrenic serial killer, who killed six people in the span of a month. He believed that he needed to prevent Nazis from turning his blood into powder via a poison they had planted beneath his soap dish.

According to Crime Library, Chase liked to set fires as a child and torment animals . In 1976, his attempt to inject rabbit blood directly into his body made him very sick, and he ended up in a mental ward. In the summer of 1977 several neighbourhood pets became victims of Chase's thirst. Using blenders, he'd mix up blood-and-guts cocktails, but soon it was not enough.

Chase was found guilty of six counts of first degree murder and was sentenced to die in the gas chamber. On 26 December 1980, Chase hoarded the anti-depressants offered to calm him and made himself disappear.

The 1988 movie "Rampage" was loosely based on Chase's crimes.

Mailwaukee Cannibal

Known as the Milwaukee Cannibal, Dahmer murdered at least 17 men and boys between 1978 and 1991. Criminal Minds claimed his murders to be particularly gruesome, involving acts of forced sodomy, necrophilia, dismemberment, and cannibalism. Dahmer committed his first murder when he was 18, killing Steven Hicks, a 19 year old hitchhiker, who was invited to his house, and killed because he "didn't want him to leave."

Unlike most serial killers, Dahmer's fantasies included a series of crimes against the corpse of his victims, or what he referred to as passive sex. This became part of his regular pattern and possibly the one obsession that pushed him to kill.

The Werewolf of Wysteria

Albert Fish, also known as the Gray Man, the Werewolf of Wysteria, and Brooklyn Vampire, boasted that he molested over 100 children, and was a suspect in at least five killings. His teen years were filled with bizarre and disturbing behaviours, Prairie Ghosts revealed, including commonly eating feces and drinking urine. At the age of 20, he began raping young boys in Manhattan where he had moved with his mother.

Fish tortured, mutilated and murdered young children with what he termed his "Implements of Hell", which included a meat cleaver, a butcher knife, and a small handsaw. He said that he liked children because they tasted the sweetest: "I never ate any roast turkey that tasted half as good".