Sub-Zero was a heartless assassin and member of the Lin Kuei. The Lin Kuei were a secret clan of theives and assassins who were based in the northern most parts of China. The clan had existed for centuries, and thrived on the evil intentions of those who payed for their services. Lin Kuei warriors were chosen at birth to be raised apart from everyday civilization and were stripped of their former lives and identities. Only the clan retained knowledge of their existance. Each possessed certain skills which set themself apart from normal men, and these abilities were passed down from generation to generation.
Sub-Zero was a fifth-generation Lin Kuei warrior, and possessed a special ability of his own. He had the ability to lower the temperature of the air around him, freezing the water molecules in the air thus forming ice. He first learned of his extraoridinary ability as a young adult. It was passed down to him by his father, also a Lin Kuei warrior. He had already recieved a lifetime of martial arts training, and applied his newfound talent to become one of the most skilled members of the clan.
A short time after he became a full-fledged member of the clan, Sub-Zero was given his first major assignment. A mysterious sorceror named Quan Chi hired Sub-Zero to infiltrate the Shaolin temples and steal the sacred Map of Elements. Sub-Zero accepted the assignment, and journeyed to the temples to obtain the mystic item. When he arrived, he found that a Japanese ninja named Scorpion was also searching for the map. The ninja were the mortal enemies of the Lin Kuei, so Sub-Zero was determined to claim the map before Scorpion. They both reached the map room at approximately the same time, and began to fight for possession of the map. Scorpion was a skilled warrior, but Sub-Zero possessed super-human abilities and emerged victorious. He slew the defeated ninja, and took the map as his own.
Returning to the Lin Kuei headquarters, Sub-Zero presented Quan Chi with the map, only to learn that he had hired Scorpion as insurance. Enraged, Sub-Zero was nonetheless pleased to find that Quan Chi had eradicated Scorpion's entire clan as a reward for Sub-Zero's success. He was given another commision from the sorceror, to travel to the Temple of Elements and retrieve the amulet of Shinnok. Sub-Zero journeyed to the hidden temple, whose location had been revealed by the map, and eventually procured the amulet. This he also presented to Quan Chi, who quickly vanished. Shortly thereafter, Sub-Zero was visited by Rayden, who revealed to Sub-Zero that Quan Chi was a source of great evil, and the amulet would give him the power to overtake the Earth.
Rayden sent Sub-Zero to the Netherrealm, the realm of Shinnok, to undo the damage he had done. With the help of Quan Chi's treacherous assassins, Sub-Zero infiltrated the sorceror's stronghold. Defeating Quan Chi, Sub-Zero found himself facing Shinnok himself. A fallen Elder god, Shinnok possessed great power, but was strangely defeated by the mortal Sub-Zero. Obtaining the amulet (which was later discovered to be a forgery), Sub-Zero was whisked through a portal back the Earth realm. He returned the amulet to Rayden, who destroyed it to end Shinnok's threat forever. Sub-Zero then returned to the Lin Kuei headquarters, exhausted from his long journey.
Not long after his trip to the Netherrealm, Sub-Zero recieved another strange commission. Another sorceror named Shang Tsung hired Sub-Zero to compete in the Shaolin martial arts tournament. Shang was the host of the tournament, and he wanted the strongest fighters to compete. Sub-Zero accepted the offer, but was given a secret assignment by his leader to assassinate Shang Tsung. With his hidden assignment in mind, he was taken to Shang's hidden island to participate. Once there, he encountered a shocking sight: Scorpion, the ninja he had killed earlier, was also an entry into the tournament. Scorpion confronted Sub-Zero, and revealed that he had been resurrected to take revenge on his assassin. Sub-Zero, undaunted by the vindictive spectre, vowed to kill him once again.
Scorpion and Sub-Zero met during the tournament, and the two began a vicious battle. Although Sub-Zero had readily defeated Scorpion earlier, the ninja was now a ghost and possessed new abilities and greater strength. Sub-Zero was defeated and killed by the stronger opponent. Although it seemed that the legend of Sub-Zero had died, his younger brother would soon rise to take the mantle of Sub-Zero.