Cerberus thanks you for all your hard work.
~ Kai Leng taunting Commander Shepard on Thessia.
Good. You opened this message. This isn't actually asari military command. They're busy tending to what's left of their planet. So you survived our fight on Thessia. You're not as weak as I thought. But never forget that your best wasn't good enough to stop me. Now an entire planet is dying because you lacked the strength to win. The legend of Shepard needs to be re-written. I hope I'm there for the last chapter. It ends with your death.
~ Kai Leng's 'Evacuating Thessia' message to Commander Shepard.

Kai Leng is the main antagonist in Mass Effect: Foundation, Mass Effect: Retribution and Mass Effect: Deception, and the secondary antagonist and final boss in Mass Effect 3.

Leng is a Cerberus assassin and also a former N7 operative and Lieutenant of the Alliance military while acting as arch-enemy for Shepard. Like the vast majority of Cerberus, he is incredibly racist towards aliens.

He is voiced by Troy Baker, who also voices Joel, Schneizel el Britannia and Pagan Min.


Early Life


While little is known about Kai Leng's early life, Alliance records show that he enlisted into the Alliance military on November 14, 2172 at the age of sixteen, though his credentials were faked at the time. Leng's prowess in combat and xenophobic nature brought the attention of the Illusive Man, and Cerberus helped liberate Leng from prison after he was incarcerated for murder. Leng subsequently joined the organization and soon became one of the Illusive Man's best operatives, working as an infiltrator and assassin. He received cybernetic modifications in terms of Phantom-class implants.

Tours of Duty

  • 2172: Terminus Systems. Patrol and reconnaissance.
  • 2173: Exodus Cluster. Patrol and reconnaissance. (Reprimanded for taking medals from dead enemy officers; sentence was reduced in light of previous, exemplary service record)
  • 2174: Raid of Entiyon. (Recommended for Systems Alliance Medal of Valor)
  • 2175: Kite's Nest. Tactical reconnaissance. (Accepted into Interplanetary Combatives Academy)
  • 2176: Received N7 designation from Interplanetary Combatives Academy.
  • 2176: Dishonorably discharged and imprisoned for 20 years in an Alliance prison after charge of first-degree murder. (While on leave, murdered a krogan in a bar on the Citadel using a standard-issue service blade)

Mass Effect: Retribution

Kai Leng is sent to capture a former member of Cerberus called Paul Grayson and later murders him when Reaper tech indoctrinates him and makes him too dangerous to live. In Deception, he is tasked with retrieving Paul Grayson's body from the Citadel.

Mass Effect 3

He is among the Cerberus forces attacking the Citadel during the attempted coup. He encounters Commander Shepard whilst attempting to assassinate the salarian councilor, but is stopped by Thane Krios or Major Kirrahe; if neither are alive at this point, Leng succeeds in his assassination. He pursues the rest of the Council, who are being lead into a trap by the traitorous Councillor Udina. However, when Shepard makes it to the councilors ahead of him, Leng decides that the coup has failed and abandons Udina, who is subsequently killed either by Shepard or the Virmire survivor. He reports the failure to the Illusive Man, who writes Udina off as "expendable" and orders him to return to be briefed regarding the other plans he has set in motion.

Leng next appears on Thessia where he takes the Prothean VI containing data on the Catalyst from Shepard. Following the mission, Shepard receives a message from Asari Military Command regarding the evacuation of Thessia; upon opening the message, it is revealed to have actually been sent by Leng, who taunts the commander over their failure to stop him.

Specialist Samantha Traynor manages to trace Leng to Sanctuary, a refugee center on Horizon, which turns out to be a Cerberus facility used to study Reaper indoctrination. The Illusive Man had ordered Leng to Sanctuary in order to retrieve the research data from the facility, but by the time Shepard arrives, he has already left. During his mission, Leng encounters Miranda Lawson, who is at Sanctuary to rescue her sister Oriana from their father Henry, who is the head of operations at the facility. Depending on how Shepard handled their interactions with Miranda, she will either succumb to her injuries from her encounter with Leng, or survive due to Shepard reading Leng's dossier. Regardless of her fate, she manages to place a tracking device on Leng without his knowledge, giving Shepard the location of the Illusive Man's headquarters.

Leng makes his final appearance at Cronos Station; which is Cerberus headquarters, where he faced off Shepard and the squad in the Illusive Man's office during the Alliance Navy's assault. Leng is eventually overwhelmed and killed by Shepard and the VI is recovered. Shepard can either dedicate the kill to whoever dies by Leng's hand during the game or instead deliver a taunt on Leng.



  • Leng is written as an evil counterpart to Shepard. Both are former N7 operatives and the best fighters of their respective organizations (the Alliance/Council for Shepard and Cerberus for Leng). However, while he shows a tremendous amount of hatred towards aliens, the fate of the galaxy hangs on Shepard's ability to rally the other races to fight against the Reapers together. His cybernetic upgrades further parallel them.
  • While being primarily Chinese in heritage, he is also of Slavic descent.
  • In early concept he was supposed to be a mechanized soldier, later his appearance was designed to look more like a human version of Thane Krios; they even fight once.
  • In cutscenes, he becomes invisible and summons a force field, but not in game play despite having the same implants as Cerberus Phantoms.
  • He is easily one of the most hated villains in the series, if not the most hated. As a result, the button prompt where Shepard breaks his sword before gutting him with an omni-blade is widely regarded as one of the most popular in the series.


           Mass Effect Villains

Reapers and Servants
Sovereign | Harbinger | Human-Reaper Larvae | Saren Arterius | Matriarch Benezia | Husks | Collectors

Illusive Man | Renegade Commander Shepard | Kai Leng | Oleg Petrovsky | Henry Lawson | Maya Brooks | Gavin Archer

Corrupt Party Members
Jack | Morinth | Zaeed Massani

Villainous Organizations and Species
CAT6 | Geth | The Citadel Council | The Blood Pack | The Blue Suns | The Eclipse | The Archon

Mercenaries and other Criminals
Aria T'Loak | Captain Enyala | Clone | Doctor Saleon | Garm | Golo'Mekk vas Usela | Harkin | Jaroth | Jedore | Ka'hairal Balak | Nassana Dantius | Shadow Broker | Tarak | Tela Vasir | Vido Santiago | Warden Kuril

Other Villains
Admiral Daro'Xen | Admiral Han'Gerrel vas Neema | Clan Chief Weyrloc Guld | Dalatrass Linron | Gatagog Uvenk | Maelon Heplorn | Ronald Taylor | Thorian | Urdnot Wreav

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