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KOS-MOS Ver. 3 in Xenosaga Episode III

Mary Magdalene
Princess of First Division
Assistant Number 3 (by Professor)
T.C. 4765
Carioca (Archetype)
Hair color
Light blue
Eye color
Blue (as Mary)
Voice actor (Japanese)
Mariko Suzuki
Voice actor (English)
Bridget Hoffman (I, III)
Colleen O'Shaughnessey (II)
Luci Christian (anime)
Shion, you forget I am not human. I am merely a weapon. You of all people should be well aware of that fact.
—KOS-MOS, after being asked if she has a conscience by Shion.

KOS-MOS is an armored android robot combat weapon with an artificial intelligence designed to fight the Gnosis, developed by the interstellar conglomerate Vector Industries First R&D Division and completed in the year 4767 T.C., created by Kevin Winnicot and administrated by Shion Uzuki.

Kevin built KOS-MOS for the purpose of "Eternal Recurrence", for the vessel of Mary Magdalene, the partner of Jesus Christ.

She is comprised of entirely mechanical parts (possibly from a superior breed of complex nanomachines), a rarity in the age of advanced Realian technology. The basic tenet to which she adheres is based on logic, probability, and completion of her mission above all else. She also unconditionally protects Shion. She is equipped with a "Simulated Personality OS" to aid in communication, and though her speech conveys her role as a robot in service to humans, her tendency to put logic and probability first makes her quite difficult to manage at times. She appears to be emotionless, but throughout the series, evidence indicates that this is not entirely true.

The name 'KOS-MOS' is a recursive acronym used to denote an Anti-Gnosis tactic system. It stands for "Kosmos Obey Strategical Multiple Operation System". Her development name is "KP-X", and she is self classified as a "Special Humanoid Anti-Gnosis Annihilation Weapon". Her serial number is "00-00-00-00-1". Her password is "Ye shall be as gods".


Archetype Edit

Kevin wanted KOS-MOS to have a female form as opposed to a male form because he wanted KOS-MOS to symbolize hope and healing, as well as a creator and protector.[1] A female form would also be more suitable for Mary Magdalene.

Xenosaga Episode I HD Cutscene 056 - The KOS-MOS Incident - ENGLISH03:19

Xenosaga Episode I HD Cutscene 056 - The KOS-MOS Incident - ENGLISH

KOS-MOS Archetype killing Vector and U-TIC employees.

Kevin was killed approximately two years before the events of Xenosaga Episode I, T.C. 4765, in an accident that involved KOS-MOS booting up independently and murdering several members of the team assigned to build her by Vector's Second Division on planet Carioca. Shion and Allen Ridgeley survived the attack and decided to continue the project without Kevin.

KOS-MOS's new frame was put together by Shion and the others after transplanting the core module of the partially-destroyed Archetype into a spare frame. Partially in order to shake off memories of the incident when the Archetype went out of control, the exterior of KOS-MOS's design was much closer to that of a human body. Several monitoring sensors were installed inside of the body to record real-world data.

Design and functionsEdit


KOS-MOS breast cannons in Super Robot Wars OG Endless Frontier.

KOS-MOS has significant powers believed to be superior to all other party members, with the possible exception of Jr.'s Red Dragon Mode.

In addition to superhuman strength and speed, her body is formed from some sort of highly advanced nanomachines that allows her to morph parts of her body (specifically her arms) into various energy projectile and melee weapons. This body is also able to self-repair and is very durable though not indestructible, and she is also protected by a force-shield.

She also possesses the ability to summon weapons such as the F-G-SHOT gatling guns and her famous F-SCYTHE and equipment without the use of the U.M.N.

She has a long-range sensory array, the D.S.S.S. system and CPU that either rivals or exceeds even those possessed by Observational Realians.

She possesses the Hilbert Effect but its power is easily thousands of times greater than that achieved by even the largest spaceships.

KOS-MOS possesses several black box components left behind by Kevin since the current KOS-MOS is essentially the archetype resurrected. There are still many 'black boxes" to be revealed but two include her potent "X-buster" a weapon that fires powerful energy beams from her abdomen as well as absorb Gnosis, and components that her give her some kind of self-awareness. KOS-MOS also has some form of energy manipulation tied to the Zohar.

KOS-MOS has one last weapon system called the Tertiary Weapon System, which is seen periodically throughout the series. They consist of a set of energy wings, a pair of energy cannons and other attachments meant to be fitted onto her. The wings and cannons are part of a Phase Transfer Cannon. While wearing this gear she is shown in a premonition flying through space at sub-light speed and then confronting U-DO above an unknown planet. The exchange that follows destroys several planets. The "Third Armament" as its also known makes a real-time appearance in Episode II on the Omega System. KOS-MOS uses this equipment to protect Shion and the party from a U.M.N. Phase Transfer Cannon fired by Proto Omega.


Shion Uzuki calibrating KOS-MOS.

There is evidence to suggest that a failsafe that dampens KOS-MOS' output is present when she battles alongside Shion, as her reflexes and combat capability are severely lowered compared to that of cutscenes (a notable example of this is the useage of her X-BUSTER in Episode I, where it has a significantly decreased effect in battle when compared to its usage outside the Cathedral Ship). This may be due to KOS-MOS' programming preventing her from doing anything to place Shion in danger, and that unleashing her full potential with Shion nearby is likely to get her caught in the crossfire.

Finally, KOS-MOS also has the ability to dance.[2]

Blue-Eyed KOS-MOSEdit


Blue-Eyed KOS-MOS in Episode III.

An almost human alternate persona (Mary Magdalene) tends to come out from time to time in the form of a blue-eyed KOS-MOS. Blue-eyed KOS-MOS appears to be more powerful than red-eyed KOS-MOS and talks in a more human-sounding voice. This form of KOS-MOS only seems to appear at times when Shion is in extreme danger. Therefore, this version of KOS-MOS plays the role of Shion's guardian. Shion has not directly seen KOS-MOS in her blue-eyed form and is oblivious to this second persona's existence until Episode III.

Blue-eyed KOS-MOS has made four appearances in Xenosaga:

  • Wiping out a fleet of Gnosis surrounding the Cathedral Ship with her X-Buster attack. Blue-eyed KOS-MOS also asked Shion during her first appearance in Episode I, "Will feeling pain make me complete?", though Shion couldn't give her an answer because she could not hear KOS-MOS' voice in the vacuum of space.[3]
  • Saving the Elsa from burning up in the Second Miltian atmosphere.
  • Saving Shion and Allen Ridgeley from being killed by Voyager, the Black Testament.
  • Saving Shion in the finale of Episode III.

Xenosaga Episode IEdit


KOS-MOS Ver. 1 in Episode I

Virgil the Conductor11:05

Virgil the Conductor

KOS-MOS saves Shion.

During a Gnosis attack on the Woglinde, KOS-MOS is activated suddenly and the Gnosis escape with the Emulator. Galaxy Federation Lieutenant Luis Virgil is shot and killed by KOS-MOS during these events; this, according to her, was necessary due to the fact that it would increase her ability to protect Shion.

After the Woglinde is destroyed, Shion, Andrew Cherenkov, Allen Ridgeley, and KOS-MOS are rescued by the Elsa starship, which was investigating the ruins of the starship from the Kukai Foundation. On the Elsa, the group encounters a mysterious boy, chaos, before asking Captain Matthews to escort them to Second Miltia.

Later, the Galaxy Federation places charges on the Kukai Foundation for the destruction of the Woglinde, due to some manipulation by U-TIC Organization officials and insiders. In order to prove innocence, Shion Uzuki leads a dive into the Encephalon to find KOS-MOS' black box, which will prove that the Gnosis were responsible.

In the Encephalon, the party relives childhood memories, including the Miltian Conflict. Shion is encountered by Febronia, who explains that a time will come where KOS-MOS will encounter the wave existence U-DO, and in the near future, Shion will free her "sisters", Cecily and Cathe. Febronia also states that all factions involved must travel to Old Miltia. Shion then finds KOS-MOS crucified in a cave (Rennes-le-Château), in front of a tomb containing Mary Magdalene's body.

Xenosaga Episode I Escape05:41

Xenosaga Episode I Escape

KOS-MOS stays to disassemble the Proto Merkabah.

When MOMO Mizrahi is kidnapped by Albedo during the Kukai Foundation evacuation, she is taken to the Proto Merkabah. On the Proto Merkabah, the party encounters Albedo, who summons a Gnosis called Sophie Peithos to "test" the party and give him time to escape. Albedo sets Merkabah on a collision course with Second Miltia, which the party stops by breaking the space station into thousands of pieces. However, during re-entry, the Elsa's heat shield begins to disintegrate; KOS-MOS briefly morphs into a powerful being to prevent the Elsa from being destroyed.

Xenosaga Episode IIEdit



In Episode II, KOS-MOS has little effect on the plot and is simply a supporting character.

At Second Miltia's Vector Industries headquarters, Shion, Allen Ridgeley, and KOS-MOS are briefed of the increasing Gnosis threat.

KOS-MOS receives a new frame created by the Second R&D Division on Second Miltia during the KOS-MOS OS tests. In order to shield her internal organs from shocks delivered to the outer body during combat, her body was filled with fluorescent blue anti-G gel. The Hilbert emission device, which had taken the form of a visor in Version 1, was miniaturized and installed into her forehead. Her body was designed with the implementation of the Tertiary Weapons System in mind; its resilience was increased dramatically.

Her data is sent to the Encephalon dive while at the R&D Division.

In Labyrinthos on Old Miltia, KOS-MOS destroys Cecily and Cathe, freeing them from their suffering.

Xenosaga Episode IIIEdit

Vector Industries decides to terminate the KOS-MOS program in favor of the newer and more advanced T-Weapon Program that resulted in the development of T-elos. Seeing KOS-MOS as an expendable asset, she is used as a live-fire opponent for the new Omega machine. In the fight KOS-MOS utilizes nearly every attack in her arsenal including her X-Buster but is unable to destroy the enormously larger Omega. She appears however to have some effect as Omega malfunctions during the fight, and it is forced to cancellation. When T-elos is demonstrated as being superior, KOS-MOS is ditched in a garbage compacter. There she is found and reactivated by Shion, and company.

KOS-MOS continues to travel with the group until doing battle with T-elos in Rennes-le-Château. The two engage in a pitched battle, in which KOS-MOS is completely dominated by T-elos. KOS-MOS only manages to connect with a single attack against T-elos while taking severe damage herself. Finally T-elos utilizes her Phase Transfer Cannon, which KOS-MOS attempts to deflect. Her effort fails and she sustains crippling damage from the attack. T-elos completes the fight by driving her heel through KOS-MOS chest as she lay on the ground. As KOS-MOS lay "dying" Shion has a vision of Mary Magdalene as she stares at T-elos.



When KOS-MOS is examined by Shion, Allen and the Professor, they come to the conclusion that KOS-MOS will never again be operational due to the severe damage. This outcome changes when Shion is able to obtain the original design data from a past Kevin Winicott (unknown to him) while masquerading as U-TIC personnel. Then with the assistance of the professors Erde Kaiser technology KOS-MOS is rebuilt into her Version-IV form. The new KOS-MOS is considerably more powerful, and awakes to protect Shion when she is attacked by the Testament Voyager. Her rebuild also grants KOS-MOS the ability to reject the commands and directives of Kevin Winicott, something she was incapable of before.

It eventually becomes clear that KOS-MOS was the prototype for T-elos, who in turn was intended to serve as the vessel for the resurrection of Mary Magdalene. KOS-MOS came to be the repository for Mary's spirit, while T-elos was constructed from the remains of Mary's body. In order for the resurrection to be complete, one would have to destroy the other. All of this fit in with the plan master-minded by Wilhelm to use Mary Magdalene's power to operate Zarathustra and "reset" the progression of time in the universe back to an earlier stage. It was this very activity that lead to the creation of the Gnosis as eventually human spirits began to reject the repetitive existence.

KOS-MOS has a final showdown with T-elos as Shion and the group make their way to Zarathustra on Michtam. At first the fight proves a stalemate, as T-elos is unable to completely overwhelm the rebuilt KOS-MOS as she did before. In the second fight KOS-MOS is able to completely evade T-elos attacks, but fails to land any of her own. Finally T-elos resorts once again to her Phase Transfer Cannon. As before KOS-MOS attempts to deflect the blast, and this time is successful doing so with only one hand. T-elos then fires a second, much more powerful shot. KOS-MOS answers by revealing her own Phase Transfer Cannon and returning fire. The two weapons meet, with T-elos weapon being overcome. T-elos is then encased in the array, and KOS-MOS utilizes a knife to shatter the globe. This is sufficient to disable T-elos. (Perhaps even kill her as she does not move or speak afterward). Following this the two begin to resonate with one another as KOS-MOS kneels and takes T-elos in her arms. T-elos dissipates into particles which are taken in by KOS-MOS. This completes Mary's Resurrection with the merging on body and spirit.

The new entity however is not a complete recreation of Mary Magdalene. KOS-MOS states that she is both Mary, and not Mary (it means she got Mary Magdalene's memory and power). After the group defeats Kevin the Red Testament they enter the chamber of Zarathustra. There Wilhelm attempts to command Mary to assist him in activating the device as he has apparently done several times before when he previously reset universal time. This time however KOS-MOS refuses and destroys the key to Zarathustra, and stating that her name is not Mary, but KOS-MOS with her eyes red instead of blue previously. It is left to interpretation if KOS-MOS and Mary are two separate entity or if KOS-MOS is the result of the merging of Mary's consciousness and her original OS.



Shion and KOS-MOS.

A violent battle then ensues as Zarathustra goes out of control. After great effort the group manages to overcome Zarathustra. Nephilim then appears stating that her and chaos will begin summoning the troubled spirits of the Gnosis and returning them to the "Land of Origin" also known as Earth. They state that they will be unable to defend themselves while handling this task. KOS-MOS stays behind to protect them in this task. KOS-MOS and Shion share final words where KOS-MOS states that they will see each other again, and that their time apart will be a mere instance in the scope of universal time.

KOS-MOS transfers a part of Mary to Nephilim. (It is not clear within the confines of what is shown if she transfers the spirit of Mary, or merely the animus power.) The group then retreats, and KOS-MOS begins fighting the many Gnosis who attempt to attack chaos and Nephilim. Fearing that not even KOS-MOS can handle the large numbers of Gnosis alone, Jin returns to give her assistance. KOS-MOS is able to destroy a large number of Gnosis before losing an arm while wounding another. Jin manages to finish the particular Gnosis off and the two continue fighting. Jin is killed after being stabbed to death, leaving KOS-MOS to finish protecting the others on her own.

She manages to hold the Gnosis off as chaos and Nephilim approach completion of their task. As they approach completion however they are attack by a Cathedral Ship type Gnosis. In an act of self-sacrifice to ensure the completion of the task KOS-MOS energizes her Phase Transfer Cannon and leaps into the cathedral ship creating an enormous explosion. She manages to attain the victory however as this gives chaos and Nephilim the time to finish.


KOS-MOS's torso drifts to Lost Jerusalem.

At the very end, KOS-MOS is seen in space. Her right arm and both her legs are gone, and what remains of her body is badly damaged. As she drifts she hears chaos' voice in her head telling her that apparently the universe still needs them. He then tells KOS-MOS to sleep until they are needed again. The final scene is of KOS-MOS closing her eyes, as she drifts through space toward the sun rising over Lost Jerusalem.


  • "Your orders, Shion?"
  • "All systems functioning normally."
  • "Engaging with maximum output."
  • "Eliminating enemy threat."
  • "Hilbert Effect active. Gnosis materialization complete."
  • "Disabling auto-safety. Destroy all targets!"
  • "My external appearance is down 5%. Shion, I need to be cleaned."
  • Allen: "The two of us'll starve to death in this pod! You can't do this!"
    KOS-MOS: "Actually, suffocation would come first."
  • "Will feeling pain make me complete?"
  • "I have confirmed that this object can be identified with a 99.99998% probability to be the Zohar Emulator that was stored onboard the Woglinde."
  • "All photon, lepton, hadron, and graviton scans read negative."
  • "Relinquish your pain unto me!"
  • "I am happy... to be of service."



KOS-MOS Archetype.

  • In Episode I, KOS-MOS also has, like MOMO's Kirschwasser outfit, her Archetype. It is found in the A.G.W.S. Hangar in the Woglinde. This is only in the Reloaded version of the game, however.

The infamous MOK-KOS.

  • The limited edition of Xenosaga Episode II includes an action figure of KOS-MOS. The action figure is called "Jashin MOK-KOS" ("Jashin" stands for "evil god" in Japanese), because its shape is terribly ugly, and spawned a meme.
  • Nearly every element of KOS-MOS' outfit, from her hair to her boots, is available as items for created characters in Soul Calibur III (Known as the "Type X" outfit).
  • In Tales of the World: Narikiri Dungeon 3, one can find an item that allows to make a KOS-MOS costume which allows her to be used in battle: interestingly, she is the only character not from a Tales game with a desperation move that requires low life to use, namely her X-BUSTER.
  • In Tales of the Abyss, the character Anise can use X-BUSTER with the help of a rare item.
  • There is a KOS-MOS costume as Downloadable Content for the character Judith in the PS3 version of Tales of Vesperia.
  • KOS-MOS (Version I), as well as Shion Uzuki and MOMO, appear in Namco x Capcom, another game by Monolith Soft.
  • KOS-MOS, in her version IV form, along with T-elos also appears in the role-playing game called Super Robot Taisen OG Saga: Endless Frontier. Her capsule is discovered in the basement of a castle, which had been recovered after it was brought into the Endless Frontier. When the main character's party finds the capsule and opens it, KOS-MOS activates, noting that the final checks on her new form were not yet complete. KOS-MOS also recognizes two members of the party, Reiji Arisu and the kitsune Xiaomu, from the events of Namco x Capcom, putting the two games in continuity with each other. T-elos also appears as an enemy in the game, though their conflict (hinted but not explicitly said to be the events of Episode III) remains unresolved by the end, where they are presumed to have returned to their home dimension.
  • She and T-elos also return in the sequel, Endless Frontier EXCEED, while this time also receiving support from MOMO. T-elos appears as an enemy, but at some point in the game joins the party as a support character as well. Both games also feature the two main characters from Namco x Capcom, whom KOS-MOS recognizes, placing the two series' in continuity with each other.
  • KOS-MOS appears as a character in Project X Zone, also by Monolith Soft, alongside T-elos.[4]


Xenosaga Episode I Edit

Xenosaga: The Animation Edit

Xenosaga Episode II Edit

Xenosaga Episode III Edit

Other Edit

Cameos Edit

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