Original timeline Edit
An exceptionally skilled warrior and one of the few chosen by the thunder god Raiden, Liu Kang became the Grand Champion of the Mortal Kombat tournament by defeating the demonic sorcerer Shang Tsung and saving Earthrealm from being absorbed into Outworld. Liu Kang has stood among Earthrealm's strongest defenders for years, protecting his world from conquerors such as Shao Kahn and Shinnok. However, he would one day fall victim to the Deadly Alliance of Shang Tsung and Quan Chi, losing his life and his soul to the villainous sorcerers.
Not long after his murder, Liu Kang's corpse would be reanimated by Raiden. In a confrontation with the newly reborn Onaga, Raiden had sacrificed his own life as he released a blast of celestial energy. This blast killed Shang Tsung - who had consumed Liu Kang's soul - causing Liu Kang and the thousands of other souls Tsung had stolen to be released. However, when the thunder god was reborn, he returned as a dark, corrupted version of his former self. This twisted version of Raiden attacked the Wu Shi Academy of the White Lotus where Liu Kang's body had been buried and reanimated the corpse as a mindless zombie.
Under Raiden's control, Liu Kang's undead corpse went on a brutal rampage, murdering many of his fellow Shaolin monks and anyone else who stood in his way. Liu Kang's spirit would come to learn of Raiden's dark reformation and how he was using his body, allying himself with the mysterious ninja Ermac so that they could stop Raiden and also free Liu Kang's allies who had been enslaved by Onaga. Liu Kang was successful in saving his friends, but Raiden still had control of Kang's body.
As Armageddon loomed, the spirit of Liu Kang, now anchored to the mortal plane by Nightwolf, intended to confront Raiden and regain his body. During the final battle, however, Nightwolf was slain and Liu Kang's soul could no longer maintain its presence in the physical world. As for Liu Kang's body, in a fit of mindless fury, it attacked and killed Shang Tsung. Raiden released his control of the corpse prior to his final duel with Shao Kahn.
Alternate timeline Edit
In the current timeline of the series, Liu Kang participated in Mortal Kombat in Earthrealm and Outworld as he had in the original timeline, achieving victory in both tournaments. However, during the Outworld Invasion of Earthrealm, Kang's destiny takes a most dire turn. His mentor and friend, the thunder god Raiden, is plagued by troublesome visions of a future where Shao Kahn brings about Armageddon. Repeated over and over in these flashes is a message sent by Raiden's future self, stating "He must win".
With the Elder Gods refusing to intervene and more Earth kombatants falling to Kahn's forces, Raiden decides to meet with the Netherrealm sorcerer Quan Chi and request his help. This decision greatly shakes Liu Kang's faith in Raiden and the monk fears that the thunder god's desperation has driven him mad.
Raiden soon returns from the Netherrealm, having deciphered the meaning of his message from the future. "He must win" actually refers to Shao Kahn; when the Outworld emperor sets foot in Earthrealm, the Elder Gods will be forced to intervene as Kahn did not achieve victory through Mortal Kombat. Liu Kang, however, believes that Raiden has snapped and that this decision will surely doom Earthrealm. He attacks his former mentor but Raiden casts lightning to protect himself. The lightning burns Liu Kang's flesh and leaves him gravely wounded. With his final breaths, Liu Kang curses Raiden, then dies in the thunder god's arms.
Due to a pact forged between Shao Kahn and Quan Chi, the souls of any warriors slain during the Outworld invasion descend into the Netherrealm and fall under Quan Chi's control. With his powers of necromancy, Quan Chi uses the souls of the dead kombatants to create a force revenant servants, among them being Liu Kang. The revenant Liu Kang, along with the revenant versions of his other fallen comrades, later join Shinnok's army of demons as they invade Earthrealm.
While Shinnok's invasion is thwarted, Liu Kang and the other revenant kombatants retreat back to the Netherrealm. It is only twenty-five years later that they reappear again as Quan Chi, before he is slain by Scorpion, reacquires Shinnok's amulet and releases the fallen god once more. Liu Kang and the other undead warriors then accompany Shinnok as he heads for the Jinsei, the source of Earth's life force. While Shinnok enters the Jinsei Chamber, Liu Kang and the revenants hold Raiden at bay. During this time, Raiden attempts to make peace with Liu Kang, stating that Kang's death has continued to haunt him. The corrupted Liu Kang dismisses Raiden's apologies, claiming that he has been freed in death. Former master and student fight, with Raiden emerging victorious and proceeding to follow Shinnok to the Jinsei Chamber.
Liu Kang is last seen some time after Shinnok's defeat. With Shinnok beaten, Liu Kang has taken the throne of the Netherrealm in his absense. He and his queen, the revenant Kitana, are greeted by Raiden, who has been corrupted after purifying the Jinsei. Raiden throws Shinnok's still-living head before Kang's feet, stating that there are worse fates than death and warns that he will no longer merely 'defend' Earthrealm, threatening to take more aggressive actions should anyone dare to endanger his world again.
Liu Kang is a master of many fighting styles including Karate, Jun Fan, Pao Chui and Monkey. He also possesses pyrokinetic abilities and can sheathe his fists in flames as well as cast fireballs. He has retained all of these abilities even in his different undead forms.