Liu Kang is the main character in the Mortal Kombat series.
About Liu Kang
According to Mortal Kombat Statistics, Liu Kang is the most popular Mortal Kombat character in the series of all, a fusion of both Eastern and Western traditions in martial arts movies. He is a Chinese Shaolin fighting monk, but his style and manners are more westernized. He moves quickly and possesses formidable fighting skills. Liu Kang is one of the best warriors of earthrealm and has beaten many to prove his valor. Throughout the series, Liu Kang has been gradually portrayed as the main hero, becoming Champion after the first Mortal Kombat tournament and then following whatever quest Raiden has in mind for him. His romantic interest is princess Kitana, but he is unable to commit himself to a relationship due to his duty of protecting Earthrealm, as the Champion of Mortal Kombat, while Kitana has to stay in Edenia/Outworld as reigning princess.
Liu Kang was brutally murdered by Shang Tsung (who had Quan Chi's assistance) in the prelude of Mortal Kombat: Deadly Alliance, his soul consumed by Tsung. He did return in Mortal Kombat: Deception, albeit as an undead corpse. He also co-stars alongside Kung Lao, Sub-Zero, Scorpion and others in the adventure game: Mortal Kombat: Shaolin Monks, and is featured again in Mortal Kombat: Armageddon.
Liu Kang follows the teachings of the shaolin White Lotus Society and was sent by the Temple of Light to defeat Shang Tsung. He desired to defeat Shang Tsung and bring the tournament back to its Shaolin owners. Liu Kang was trained by Master Bo' Rai Cho, who taught him the Flying Kick. As he made his way to the tournament, he met and became friends with Johnny Cage and Sonya Blade. At the time of Liu Kang's entry, Outworld had won nine Mortal Kombat tournaments in a row. Eventually, Liu Kang earned the right to challenge Goro to Mortal Kombat. By exploiting the Shokan's overconfidence, Liu Kang defeated Goro and became the new Champion of Mortal Kombat. Upon hearing of Goro's defeat, Shang Tsung challenged him. After an epic battle, Liu Kang defeated Shang Tsung with his Flying Kick, emerging as the new champion of Mortal Kombat.
Coming home from Tsung's Island, he found many of his Shaolin killed in a vicious attack by a Tarkatan horde. Enraged, Liu Kang decided to travel to Outworld, backed by fellow White Lotus member and spiritual brother Kung Lao, Raiden, Sub-Zero's younger brother, and Smoke to seek revenge. Before he traveled to Outworld, Liu Kang went to Hollywood to seek Johnny Cage's help.
Luckily, Liu Kang arrived at the right time as Cage was being attacked by a Tarkatan horde. Now joined with Johnny and new-found friend Jax they finally traveled to Outworld. At the tournament, he and Kung Lao met Kitana, and Liu Kang began to fall in love with her. He learned the true nature of the Outworld tournament but competed anyway. While it is unclear as to what matches took place, it is known that Liu Kang fought Shao Kahn, eventually overpowering the emperor. It is also strongly possible he also faced Shang Tsung in front of Shao Kahn, defeating him despite his youth and renewed powers, and Kintaro as well. Near defeat, Kahn ordered his forces to destroy the earth fighters, forcing Earth's heroes to return home and to begin preparing for the coming invasion.
After returning to Earthrealm, Liu Kang, along with Kung Lao, began training a new generation of Shaolin Warriors, but was interrupted when the invasion began. As Kahn's extermination squads were sent to kill Earth's chosen warriors, Liu Kang found himself the primary target. Kung Lao who went against Shao Kahn was nearly beaten to death. Enraged, Liu Kang challenged the Emperor to Mortal Kombat, and after the final battle, he defeated Shao Kahn again, causing him and his forces to retreat back to Outworld. The souls that Khan had trapped were set free and, just before the portal closed, Liu Kang was thanked by Kitana for his part in saving both Earth and her realm from Shao Kahn.
Liu Kang traveled to America to look for a new generation of Shaolin warriors to train. While there in America, he met his old friend Kai. The two then travelled back to China, where Liu Kang trained Kai to be a Shaolin Warrior. However, the peace was not to last, as the fallen Elder God Shinnok had escaped from the Netherrealm through a portal to Edenia. Upon learning that Kitana had been captured, Liu Kang set out on his own to save her, but he was unsuccessful. Liu Kang returned to Earth, where he began gathering Earth's warriors to save Earth and assist his mentor, Raiden.
Eventually, Liu Kang confronted the fallen Elder God Shinnok and once again emerged victorious, effectively ending his attack on Earth. Liu Kang returned to the Shaolin Temples, believing he has lost Kitana forever. However, the Edenian Princess appeared through a portal from Edenia and thanked Liu Kang for all he had done. She offered him a chance to join her at the throne of Edenia. However, due to the responsiblities as a Mortal Kombat Champion, Liu Kang was forced to decline her offer.
The zombie Liu Kang debuted in Mortal Kombat: Deception.
For some years, Liu Kang went on to enjoy relative peace. However, the Deadly Alliance would make itself known on Earth by its successful assassination attempt of Liu Kang. Shang Tsung posed as Kung Lao and snuck up on the champion as he was practicing his katas. Shang Tsung, was assisted by Quan Chi, who caught Liu Kang in the back unawares with a projectile. Shang Tsung used this distraction to gain the upper hand and snapped Liu Kang's neck. He then consumed his soul. Liu Kang's mutilated body was discovered by his friend Kung Lao, and he was laid to rest at the Wu Shi Academy, where a shrine was built to honor him.
In the culmination of the events of Mortal Kombat: Deception, Raiden released his godlike essence in order to destroy Onaga, presumably killing both Quan Chi and Shang Tsung in the process. While it is unknown whether or not Quan Chi and Shang Tsung are truly dead, it has been established that the thousands of souls that Tsung consumed in the past were released, including that of Liu Kang. Furthurmore Raiden, now somehow corrupted in his reformation, reanimated Liu Kang's body and sent it on a rampage, slaughtering many of Liu Kang's fellow Shaolin monks. Liu Kang's spirit decided to stay in Outworld to assist in the war against Onaga, but he soon discovered his body's "resurrection" and was stricken by what he had done. Although Liu Kang wasn't technically responsible, he couldn't help but feel responsibility for the actions committed by his corporeal form. He also learned about his comrades and how they had been enslaved by Onaga. From there, Liu Kang enlisted the mysterious ninja Ermac as an ally and had two missions to complete. The first was to try and save his friends from Onaga with Ermac, the second to defeat and stop his body from doing further harm.
In Mortal Kombat: Armageddon, he accomplishes his first task by saving his friends but was unable to reunite his body and soul. However, in his ending, players learn that upon defeating Blaze, Liu Kang's body and soul reunite, and he gains the power of a god. Liu Kang then confronted the corrupted Raiden, and reluctantly defeated him in an epic clash. With the consent of the Elder Gods, he replaced Raiden as Protector of Earthrealm.  This is either an oversight on the game's programmers or a subtle hint at the ending's canonicty- Liu Kang cannot relieve Raiden as Protector of Earthrealm as Fujin is the one who holds that position, and has done since the final moments of the Mortal Kombat 4/Gold storyline. In any instance, Liu Kang is still the reigning, undisputed Champion of Mortal Kombat.