Psycho Mantis was born in a small Russian village before the collapse of the Soviet Union. His mother died giving birth to him, which made his father resent and hate him. He discovered his powers and his father's true emotions one day while accidentally reading his mind. He wondered if his father would kill him, and the shock of this revelation awoke his subconscious. He used his telekinetic powers to burn down the village that he lived in, killing all residents. This release of psychic energy caused severe burns across his body, particularly his face.
Mantis later joined the KGB and was part of its psychic intelligence division. After the collapse of the Soviet Union, he moved to the United States and began work for the FBI. He would enter the minds of suspected killers and uncover the truth about their crimes. However, during one interrogation in the year 2000, Mantis dove too deeply into the mind of a serial killer and subsequently adopted the subject's personality, becoming psychotic.

Mantis eventually left the FBI and became a freelance psychic, offering his services to the highest bidder. During his travels throughout the world, he read thousands of peoples thoughts, and became disgusted with humanity for, as he called it, their "selfish and atavistic desire to pass on one's seed." He was eventually enlisted by FOXHOUND, becoming the unit's psychic expert and its psychological warfare specialist. By this time he had taken to wearing a gas mask, partially to hide his deformed facial features, but also to prevent the thoughts of others from entering his mind. At some point, Mantis received barcode tattoos on each of his shoulders and on the right side of his head, along with a large scar across his head.