Bo' Rai Cho's History
Bo' Rai Cho taught several great warriors, including Liu Kang, Shujinko and the legendary Muso Gonnosuke. Bo' Rai Cho originates from Outworld but has not, however, participated in a Mortal Kombat tournament, knowing that if he wins, his victory would be in the name of Shao Kahn due to his status as an Outworlder. So he instead chose to utilize his fighting skills to train Earthrealm warriors.
When his student Liu Kang was murdered by the sorcerers Quan Chi and Shang Tsung, he began training Liu Kang's fellow Shaolin Monk, Kung Lao, so that he could slay Shang Tsung. While the other Earthrealm warriors prepared for an attack against the Deadly Alliance, Bo' Rai Cho spied on Shang Tsung's palace and rescued Li Mei, another fellow native of Outworld.
During the events of Mortal Kombat: Deception, he regrouped with the surviving Earthrealm warriors led by the Thunder God Raiden and retreated.
Later, he fought against Onaga in the Battle of Armageddon, siding with the Forces of Light. As soon as the Pyramid of Argus rose, he was fighting Tanya, before the pyramid caught up to her, sending her flying. He tried to make it at the top, but Kano threw one of his knives towards his back, making him moan in pain. He soon turned and threw up on Kano and Kobra, making them slide down the stairs of the Pyramid. However, Sheeva got the advantage, and with no time, Bo' Rai Cho was punched in the face, ultimately sent flying. However, Bo' Rai Cho ultimately died, by an unknown warrior.
In the new timeline, Bo' Rai Cho came upon Kuai Liang in the aftermath of his battle with Hanzo Hasashi, seemingly at death's door once again. As Kuai struggled to drag himself up, Bo' Rai Cho told him to stop and reflect upon how he arrived here, and ask himself what it all meant. As Sub-Zero recalled his life up to that point, Bo' Rai Cho tended to his wounds and when Kuai mentioned his mission to retrieve the lost Kamidogu, Bo' Rai Cho understands it possessed him.
As Kuai laments that he will never be free, Bo' Rai Cho asks him if he still hasn't figured out what all these events up till now mean or why he is here. Helping Sub-Zero up, Bo' Rai Cho laughs heartily as Kuai contemplates hara-kiri, saying they have wine for melancholy and tells Kuai that after all he has endured, Raiden owes him a favor, much to the cryomancer's confusion.
Sometime later in Pura Bratan, Bali, Bo' Rai Cho is pleased when he meets up with Kung Jin, complimenting the young man for his quickness. Kung Jin then hands over an envelope and a pleased Bo' Rai Cho hands the thief his pay while telling him he knew his uncle and trained him before offering to recommend him to the Shaolin Temple. Kung Jin declines and as he leaves, Bo' Rai Cho reminds him that he has a warrior's heart and asks why he denies it.
Bo' Rai Cho returns to Kuai Liang as he trains, informing him of Kung Jin's success. When Kuai comments on how fast that was, Bo' Rai Cho comments that Kung Jin is talented but troubled, before musing that he will ask Raiden to keep an eye on him. Opening the envelope, Bo' Rai Cho is perplexed to see only a flashdrive with a skull and crossbones on it, though Kuai Liang declares it is time to shut down the Cyber Lin Kuei.
Bo' Rai Cho accompanies Kuai Liang to the outskirts of Shulianghu, China, where Kuai shows the master the entrance to the Cyber Lin Kuei's base, an old fallout shelter. Bo' Rai Cho promises no cyborg will escape the only exit to the base, and after questioning his student if the Lin Kuei are expecting him, Sub-Zero says he's counting on it before launching his assault.
As he waits outside while having a drink after Kuai enacts his vengeance on the cybernetic clan, Bo' Rai Cho gets caught in Cyrax's explosion, surrounding him in flames, but is saved when Kuai comes out with an ice aura around him, freezing Cho in the process. After he gets unfrozen, Kaui apologizes and Bo' says to buy him a stiff drink and they would call it even. Afterward, Sub-Zero takes time off alone as he prepares for his new responsibility as leader of the reformed Lin Kuei.
In MKX, Bo' Rai Cho is seen at the Sky Temple having a drink from his flask and waiting for the arrival of Raiden. After Raiden appears they talk about how they haven't seen each other in a long time. Bo' Rai Cho and Raiden then walk to the Jinsei Chamber, as Raiden needed to disarm a trap set by Kano.
As Raiden is recharging, flashbacks go through his head. He is awoken after hearing an explosion. Looking up Raiden sees Bo' Rai Cho being dragged away. While Raiden makes his way to Bo' Rai Cho he is tortured by Shinnok. Although Shinnok mentions that Bo' Rai Cho would die shortly after the torture, his fate is left ambiguous.