Organization XIII

Organization XIII (XIII機関) is a group of thirteen powerful Nobodies who claim to seek to reclaim their hearts and become whole again. They are the antagonists of Kingdom Hearts: Chain of Memories and Kingdom Hearts II, and all are playable in Kingdom Hearts 358/2 Days. The true Organization also appear as the antagonists of Kingdom Hearts 3D: Dream Drop Distance.

Organization XIII debuted in Kingdom Hearts Final Mix, as Xemnas was a secret boss at Hollow Bastion. The group officially debuted in Kingdom Hearts: Chain of Memories, then known as simply, the Organization. In Sora's story, the player is introduced to Marluxia, Axel, Larxene, and Vexen. In Reverse/Rebirth, Riku's story, Zexion and Lexaeus were added to the cast.

The Organization's remaining members appeared in Kingdom Hearts II as the main antagonists. In this second installment, the player meets Xigbar, Xaldin, Saïx, Demyx, Luxord, Roxas, the returning member, Axel, and the leader Xemnas. Another member of Organization XIII was added in Kingdom Hearts 358/2 Days, when Xion was added to the group.

Because all the members are Nobodies, it was originally thought that they lacked hearts, meaning they would also have no emotions. However, it is revealed during Kingdom Hearts 3D: Dream Drop Distance by Xemnas and Xigbar that it is possible for a Nobody to regain a heart over time. The original Organization members yearned to discover the secrets of the heart and fill the empty void inside themselves by gathering hearts to form Kingdom Hearts so they could become full beings again. This was due to their not being told the truth by Xemnas and Xigbar, who were the only members privy to the information. Each member was made aware of their apparent lack of emotions, and many of them pretended to have emotions, for example, Saïx's enraged battle style and Larxene's giggling and winking.

The Kingdom Hearts: Chain of Memories manga and several other media forms provided an alternative view prior to the release of Kingdom Hearts 3D: Dream Drop Distance, saying that the Nobodies of the Organization do have emotions, but are plagued by a feeling of uncertainty and emptiness due to not having hearts. The manga further displayed this "plagued" feeling by showing the members engaging in tasks such as jigsaw puzzles, cooking, and reading to try to fill their emptiness.

This group's inclusion to the Kingdom Hearts storyline marks the more mature nature of the Kingdom Hearts: Chain of Memories and Kingdom Hearts II storylines, as they introduce the concepts of duplicity among the villains, minor physical abuse, manipulation of sentimental matters, and on some level, real death (the Heartless invasion of Hollow Bastion, which was Organization XIII's doing, inadvertently incapacitates Goofy for a short time, leading even the player to falsely believe that he is dead).

Origin
Organization XIII was formed by a group of scientists working under a man called Ansem the Wise, the ruler of Radiant Garden, and worked from Ansem's castle, Hollow Bastion. The head of this group was Ansem's apprentice, Xehanort, with the others being Braig, Dilan, Even, Aeleus, and Ienzo. Ansem the Wise began initiating tests about the human heart, focusing mainly on Xehanort, with the hopes of recovering his lost memories. At the urging of Ienzo, he constructed a massive laboratory under the castle. However, Ansem the Wise soon ceased his experiments, for he feared that going too deep would have grave repercussions, also noting Xehanort's apparently-superhuman abilities.

However, his six apprentices, still seduced by the desire for knowledge, conducted their own dangerous experiments on countless subjects. Eventually, they discovered the beings called Heartless, those that are born from the darkness in a heart and seek others as well. Xehanort, having taken on Ansem's name and writing his findings under it, opened a door he discovered, breaking down the barriers between worlds and allowing travel between them. When a king named Mickey arrived, the six men's desire for knowledge eventually caused Xehanort to abandon his body, becoming a Heartless (though he was unusual in that he had a human form and retained his memories), with the other five soon following. Thus, the first six members of Organization XIII were born, and they banished Ansem to a Realm of Darkness.

Kingdom Hearts: Chain of Memories
The Organization make their first appearance in the series (apart from Xemnas's appearance in Kingdom Hearts Final Mix). The neophytes, Marluxia and Larxene, tried to take control of the Organization by using Sora as their puppet by having Naminé rewrite his memory, while the senior members, Zexion, Lexaeus, and Vexen, tried to oppose them by using the darkness in Riku. However, all of them, save Axel, who was sent to kill traitors in the group, were eliminated.

Kingdom Hearts 358/2 Days
The story largely focuses on Roxas's time as a member of the Organization XIII, and thus, all the members are present here. This, Kingdom Hearts coded and Kingdom Hearts Birth by Sleep are the only installments to date where the fourteenth member, Xion, is ever mentioned due to any memories of her becoming faded since she was a being of memories that ceased to exist.

Kingdom Hearts II
Only eight members (Xemnas, Axel, Demyx, Xaldin, Xigbar, Luxord, Saïx, and Roxas) of the Organization remained at the beginning of Kingdom Hearts II. Sora and his friends took every single remaining member down, save Roxas, who became one with Sora, and Axel, who sacrificed himself so that Sora and his friends could save Kairi. In the end, Organization XIII is ultimately destroyed when Sora and Riku defeat Xemnas.

Kingdom Hearts Birth by Sleep
While Dilan, Even, Aeleus, Ienzo, Isa, and Lea appear in the game in minor roles, Braig serves as a major player in Master Xehanort's ruthless ambitions, acquiring his signature scars and eyepatch following a battle against Terra. Of Ansem's apprentices, Braig plays the largest role overall in the story until the appearance of Xehanort. Axel, Roxas, and Xion also appear in the game's secret ending, and Xemnas appears briefly in the Final Mix version of the game.

Kingdom Hearts coded
A Data version of Naminé reveals to a Data Sora that Axel, Roxas, and Xion, while apparently gone, are still connected to Sora's heart and waiting for him to rescue them from their suffering. The three appear along with Terra, Aqua, Ven, and the real Naminé as apparitions waiting for Sora to bring them back from non-existence.

Kingdom Hearts 3D: Dream Drop Distance
The resurrected Master Xehanort reforms Organization XIII, only consisting of several incarnations of himself from many alternate timelines. So far only known members are Master Xehanort himself, Xemnas, Ansem, Seeker of Darkness, Young Xehanort, Braig, and Isa. There are also six others whose identities are not yet revealed. Sora was supposed to be a member, but Lea saved him from being possessed by Xehanort. Master Xehanort says that someday a new Organization, which he calls 13 Seekers of Darkness, is supposed to battle against the 7 lights. The Organization soon vanished into darkness after Sora was saved.

Young Xehanort explains to Riku that they originally wanted him to be their 13th Vessel but because he has built an immunity against the darkness, like the Keyblade they chose Sora instead.

Master Xehanort mentioned that 1 of the 7 lights was in his possession - this, given that he merged with Terra, is presumably his heart, as Ventus's remains in Sora and Aqua is trapped in the Realm of Darkness.

Other former Organization members like Ienzo, Aeleus, Even, and Dilan appeared in Radiant Garden in Ansem's study during certain cutscenes. However, the fates of Demyx, Luxord, Marluxia, and Larxene currently remain unknown.

Xemnas explains that the nature of a Nobody is to gain a heart quickly after losing it. As such he states the true purpose of Kingdom Hearts was to prepare its members to be vessels of Xehanort.

Dress
Each member in the Organization is dressed in the same uniform, regardless of whether they are male or female. The uniform consists of a single black leather hooded coat. It is plainly adorned with a silver zipper and seemingly pointless silver beaded pull strings for the hood that form a semi-circle in the middle. Each member wears their zippers at differing points.

Not much is known about the under garments of the Organization. It is known, however, that they all wear hakama-esque black pants and knee high silver trimmed boots identical to Xehanort's, with the exceptions of Roxas, who wears sneakers of the same color, and Larxene and Xion, who wear a more feminized version of the boots with heels. In addition to this, they all wear short black leather gloves that end at their wrists. Some members have different looking coats, for example Axel and Demyx, whose sleeves are tight around their arms. Upon closer inspection, it can be seen that the hems of each coat are each slightly different, as well as the shoulder pads (such as those of Demyx and Xigbar, which seem to be slightly pointed).

Other known characters to wear the coat are King Mickey, Riku, Ansem, Seeker of Darkness, Ansem the Wise and moogles. Riku obtains his coat from DiZ and it is presumed Mickey also obtains it from him. It is unknown how DiZ or the moogles obtained them.

The reason that Organization XIII wears the Black Coat is so that when they eventually begin to regrow their hearts they will not become corrupted by the Darkness, which would allow Xemnas to keep up his lie to the rest of the organization and keep them under his control.

Ranking
Ranks within the Organization have little to nothing to do with power. While Xehanort's Nobody, known as Xemnas, is the strongest as well as the leader, the rest fall in the order they joined. Thus, their numbered rank is not necessarily representative of their status and power within the Organization. As the group's name describes, one would assume that there are a total of thirteen members; until the announcement of Kingdom Hearts 358/2 Days, this was true.

Besides having a numerical rank, each member also has an assigned title. The only exception to this is Xion, who is not a true member of the order. The ranks and titles are as follows:


 * 1) Xemnas (The Superior of the In-Between): Controls Sorcerers, uses the attribute of Nothingness and weapons called Ethereal Blades which he himself calls Interdiction. Nobody of Xehanort.
 * 2) Xigbar (The Freeshooter): Controls Snipers, uses the attribute of Space and Arrowguns called Sharpshooters. Nobody of Braig.
 * 3) Xaldin (The Whirlwind Lancer): Controls Dragoons, uses the attribute of Wind and six Lances called Lindworm. Nobody of Dilan.
 * 4) Vexen (The Chilly Academic) uses the attribute of Ice and a Shield called Frozen Pride. Nobody of Even.
 * 5) Lexaeus (The Taciturn Stalwart) uses the attribute of Earth and an Axe Sword called Skysplitter. Nobody of Aeleus.
 * 6) Zexion (The Cloaked Schemer) uses the attribute of Illusion and a Lexicon called Book of Retribution. Nobody of Ienzo.
 * 7) Saïx (The Luna Diviner): Controls Berserkers, uses the attribute of Moon and a Claymore called Lunatic. Nobody of Isa.
 * 8) Axel (The Flurry of Dancing Flames): Controls Assassins, uses the attribute of Fire and twin Chakrams called Eternal Flames. Nobody of Lea.
 * 9) Demyx (The Melodious Nocturne): Controls Dancers, uses the attribute of Water and a Sitar called Arpeggio. Original persona unknown.
 * 10) Luxord (The Gambler of Fate): Controls Gamblers, uses the attribute of Time as well as Cards called Fair Game. Original persona unknown.
 * 11) Marluxia (The Graceful Assassin) uses the attribute of Flower and a Scythe called Graceful Dahlia. Original persona unknown.
 * 12) Larxene (The Savage Nymph) uses the attribute of Lightning and eight Knives called Foudre. Original persona unknown.
 * 13) Roxas (The Key of Destiny): Controls Samurais, uses the attribute of Light, and has wielded at least three distinct Keyblades; initially wields the Kingdom Key, later dual-wielding Oathkeeper/Oblivion. Nobody of Sora.
 * 14) Xion uses the attribute of Light and the Kingdom Key. Presented as the fourteenth member, though not considered part of the Organization. An imperfect Replica of Roxas, created from Sora's memories of Kairi.

Each of the titles correspond to whichever element the particular member controls, a particular trait, or the type of weapon they have.

Differences
There are a few major differences between the Nobodies within the Organization and the ones that Sora frequently encounters throughout the game. The average type that Sora fights often have strange features, enhanced speed, metallic skin in shades of white, silver, and blue, and the trademark Nobody symbol (which doubles as the logo for the Organization).

The Nobodies that make up the Organization have human forms with limited special powers, revolving around thirteen different elements. One ability shared by all the members is the power to summon an oval, obsidian portal of darkness that leads to the unseen paths of darkness. These portals are known as Corridors of Darkness. The Organization makes use of the paths to move to and from worlds unseen without fear for their well-being compared to those who are attuned with darkness and still have hearts.

Lesser Nobodies
A few select members of the Organization have control over the other, weaker Nobodies, though this is only shown in Kingdom Hearts II  and mentioned in Kingdom Hearts 358/2 Days. The members from Kingdom Hearts: Chain of Memories may also have had that ability; this is an unknown fact left hidden with their deaths. Like their titles, each member's lesser Nobody has some similarity to them. These lesser Nobodies are called Sorcerers, Snipers, Dragoons, Berserkers, Assassins, Dancers, Gamblers, Samurai, and Dusks.

Sorcerer Nobodies are under the command of Xemnas. They float over the ground constantly, possessing a grace much like that of Xemnas, and utilize large cubes of nothingness in several ways. They are the most powerful and rarest of the lesser Nobodies.

Sniper Nobodies are controlled by Xigbar and, like him, carry spiky guns that shoot small red crystallized lasers.

Dragoon Nobodies are controlled by Xaldin because of his affinity with wind, and possess a singular lance that mirrors the six that he fights with.

Berserker Nobodies are under Saïx's power and, as with the previously mentioned lesser Nobodies, hold a weapon identical to that of their master. An observant player will also notice that Berserker Nobodies go through random surges of anger, much like Saïx when he draws upon the power of the moon.

The Assassin Nobodies are under Axel's control, capable of becoming a circular form similar to Axel's weapon, hiding away for short periods of time before attacking, and causing powerful explosions.

Dancer Nobodies are the most colorful of all the lesser Nobodies, featuring bright colors such as orange and pink. They are Demyx's servants and relate to him due to his musical and unorthodox nature.

The Gambler Nobodies are under Luxord's rule. Luxord, being a gambler of many things, fights with cards, which they use as well, along with several dice.

Samurai Nobodies are controlled by Roxas. Samurai wield two katana just as Roxas wields two Keyblades, Oathkeeper and Oblivion.

Dusks appear to be the least of the lesser Nobodies, and it appears that any recognized Organization member can control them. They are the only Nobodies known to speak, and can identify past Organization members as well. A known punishment for the Organization members is the threat to be turned into a Dusk; how this is done and if it ever has been done is unknown.

The Lesser Nobodies are named after recurring Final Fantasy job classes and share similar traits with them, such as the Dragoons ability to jump.

Naming
A common thread between all of the members is the "X" that appears within each of their names. As revealed by Tetsuya Nomura, the director of the game, by removing the "X", the remaining letters form an anagram of the members' original names from when they were humans. For instance, "Roxas" is an anagram of "Sora", and "Xemnas" is an anagram of "Ansem". Xemnas's true name is Xehanort; his name is an anagram of 'no heart' or 'another' with an X added. Xion, being an artificial Replica, had no original name. The name "Xion" came from her label as Replica No.i of the Replica Program.

Such thoughts made many fans anxious to try and figure out for themselves the rest of the Organization's members' names. The name of the Nobodies' "other" appears before them in translucent, rainbow colored font (similar to the one shown at the intro to "The World That Never Was"). Then, an "X" drops down and the letters re-arrange themselves until they form a new name, and it is suggested that Xemnas also initiates this ceremony. This has only been seen initiated with Roxas, though. Many have suggested that this isn't true, as Xigbar was the one who found Marluxia and named him, but if one listens to the dialogue between Zexion and Xigbar in Kingdom Hearts II Final Mix, it is apparent from the way Xigbar does not know how to pronounce Marluxia's name that he was not the one to name him, rather just found him.

Despite this, however, the reason for the placement of the "X", also known by Xemnas as the "Recusant's Sigil" in the naming process of a new Organization XIII member has to do with Master Xehanort, one of Xemnas's original two personas, and his fascination with the legendary χ-blade. As Xemnas regained memories of Master Xehanort's past, he remembered the χ-blade, and incorporated the "X" into Organization XIII. Another more sinister purpose of the Sigil is its apparent tracking abilities, as the presense of the sigil on Sora allowed Xehanort to track his every move. The Sigil being in the names of the Organization members would allow Xemnas to keep an eye on them at all times, which would explain how he was seemingly aware of the traitorous actions of Marluxia.

Where Nothing Gathers
Somewhere in The Castle That Never Was, inaccessible to the player, is the meeting room of the Organization. This area can be accessed with a cheat code, though—the platform with the Organization symbol can be walked on, but none of the thrones can. The game calls the area "Where Nothing Gathers"—suggesting it may have been in the final game as a full area, but was dropped later.

It is a white cylindrical room with thirteen extremely tall white thrones. The height of these thrones is determined by the amount of missions the respective members complete and the height tends to change depending on the success or failure of those missions. However, Xemnas's throne is always the highest as he is the leader and therefore has completed the highest amount of missions. To his left are the odd-number ranked members while to his right are the even-numbered. Starting from Xemnas, clockwise: Xaldin, Lexaeus, Saïx, Demyx, Marluxia, Roxas, Larxene, Luxord, Axel, Zexion, Vexen and Xigbar.

Ironically, Vexen, Lexaeus, and Zexion have the lowest chair heights out of the whole Organization.

In the new cutscenes of Kingdom Hearts II Final Mix, every time a missing member is referred to during a meeting, the camera's focus will shift briefly to that said member's throne (such as when Xaldin reminded Axel that, indirectly, he eliminated the traitors Marluxia and Larxene, the camera briefly shifts to view their thrones. The conversation concerns Axel's orders to destroy Roxas and fittingly enough, Roxas's throne is between theirs).

Proof of Existence
In the central tower of The Castle That Never Was, there is a room that is something of a graveyard or a place where beings who can't use the portal to darkness use the doorway-like portals to reach other members of the Organization. This chamber has thirteen portals which lead to a certain area throughout the castle, the portals are placed simultaneously along the walls and glow blue if that specific member is alive but red when that one is dead.

Starting from Xemnas's which is actually a path to the The Altar of Naught, going downwards are two more, then below them are four and after them are six with a path cutting half way between the portals. The portals lead to large chambers which are areas that the Organization dwell when they are resting. So far only four are known which are the Altar of Naught, where Xemnas resides and the highest point in the castle, Havoc's Divide which is a large slanted balcony were Luxord resides, Addled Impasse where Saïx lives, which is a large circular room with a balcony made of glass and looks up towards the moon, and Axel's room, who's name is unknown and is only seen in a cutscene in Kingdom Hearts 358/2 Days. Note that for gameplay purposes, the gates to Havoc's Divide and Addled Impasse remain active even after Luxord and Saïx are felled.

Also, for the same reasons, Roxas's still-active gate (since he still exists within Sora) is broken and rendered unusable, although it still maintains its blue glow. It may be broken, though, due to the fact that while Roxas still exists in Sora, he does not exist physically, or maybe because of the simple fact that he left the Organization. Note that Zexion's tombstone was especially broken to hide his weapon's image, (which was not revealed until the release of Kingdom Hearts II Final Mix+), although its lettering can still be read. Xion never had a tombstone or portal since she was a replica built by Vexen for Xemnas to absorb Roxas, which would make having a portal or tombstone of her own pointless.

Ultimate Fate
By the time of Kingdom Hearts II, the actions of Sora, Axel, Riku, and the Riku Replica, in addition to the departure of Roxas, reduced the Organization's roster to eight, which were then slain by Sora one-by-one (with the exception of Axel, who sacrificed himself to allow Sora to go and save Kairi) until only Xemnas remained. Ultimately, Xemnas fell at the hands of Sora and Riku, and Roxas (now a part of Sora once again, but still somewhat independent, as seen in the ending video before the credits) could be considered the sole surviving member. All members who originated from Hollow Bastion, save Terra-Xehanort, Braig, and Isa, were resurrected in Kingdom Hearts 3D:Dream Drop Distance.

I. Xemnas - Defeated by Sora and Riku at the end of Kingdom Hearts II. He was trying to dispose of the only threat standing between him and Kingdom Hearts. Disappeared in Darkness in what appears to be a black variation of the white Nobody thorns. He was the thirteenth, fourteenth if Xion is counted and final member to fall, but since both his Heartless and Nobody have been slain, Master Xehanort is now able to return from the darkness. During his travels Young Xehanort pulled an incarnation of Xemnas from an unknown point of time before his death into the future to become a member of the True Organization.

'''II. Xigbar''' - Defeated by Sora, Donald, and Goofy in the Hall of Empty Melodies in The World That Never Was. He started the fight to try to prevent Sora and company from ascending any farther up the castle but disappeared into Darkness. He was the ninth member to disappear, tenth if Xion is counted. Young Xehanort saved Braig from his destruction by sending an incarnation of him from an unknown point in time forwards to become a member of the True Organization.

'''III. Xaldin''' - Defeated by Sora, Donald, Goofy, and Beast at Beast's Castle. He was on a mission to turn the Beast into a Heartless and Nobody. Disappeared into Darkness and wind, and, in the manga, was killed by a Vexen Replica. Xaldin was the seventh member subject to elimination, eighth if Xion is counted. Due to his elimination, he was revived as Dilan.

'''IV. Vexen''' - Defeated by Axel as a way to gain Marluxia's trust. Vexen opposed Marluxia's plot and Marluxia wanted him eliminated. Disappeared by incineration into Darkness. He was the first member to fall. His death lead to the recreation of Even.

V. Lexaeus - Defeated by Riku while possessed by Ansem, Seeker of Darkness. He was trying to make Riku use the Darkness inside him. From what is shown in the cutscene of his elimination, he was helpless against Ansem, Seeker of Darkness due to his weakened condition after his brutal fight with Riku. He disappeared into Darkness, and was the third member eliminated. His death led to the reconstruction of his original persona, Aeleus.

'''VI. Zexion''' - Defeated by Riku Replica and Axel. Axel wanted no evidence of his actions in Castle Oblivion, so when Zexion was extremely weary from his battle with the real Riku, Axel had the Riku Replica absorb Zexion. He disappeared into gaseous Darkness while engulfed in the Replica's energy. Zexion was the fifth member to fall. His death lead to Ienzo's recreation.

'''VII. Saïx''' - Defeated by Sora, Donald, and Goofy. He was confronted simply to try to eliminate the last of the Organization. He disappeared into gaseous Darkness. He was the eleventh to be defeated, twelfth if Xion is counted. Despite fading away he was saved from his fate by Young Xehanort, who sent an incarnation of him from an unknown point of time into the future to serve as a member of the True Organization.

'''VIII. Axel''' - Eliminated in a sacrificial attack to save Sora from an army of Dusks. Similar to a fire, he seemed to "burn out" into Darkness, resembling ashes. Axel was the eighth member to fall, ninth if Xion is counted. He was later revived as Lea.

'''IX. Demyx''' - Defeated by Sora, Donald, and Goofy. He was one of the few mentionable people destroyed in the Battle of the 1000 Heartless. He confronted Sora and company just for the sake of battling in the war. He disappeared into Darkness and appeared to have boiled up and evaporated. He was the sixth member to disappear, seventh if Xion is counted.

X. Luxord - Defeated by Sora. He captured Donald, Goofy, Riku, and Kairi, forcing Sora into one of Luxord's "games." Sora was able to beat him by "winning the game" and slashing through his shield of cards. He disappeared into gaseous Darkness. Luxord was the tenth member to be eliminated, eleventh if Xion is counted.

'''XI. Marluxia''' - Defeated by Sora. He was trying to destroy Sora since he couldn't control him. Marluxia himself is never actually fought, but after Sora destroys a clone, a machine-like Nobody and an angel-like, feminine reaper, all Marluxia's energy is gone and he is beaten. He disappeared attempting to grab Sora in gaseous Darkness in a flurry of flower petals. Marluxia was the fourth member to be eliminated.

'''XII. Larxene''' - Defeated by Sora, Donald, and Goofy. She was on a mission to kill Sora after her plan fell apart. She would have succeeded, but an attempt to save Sora by Naminé, Donald, and Goofy gave him the strength to fight back, and Larxene eventually met her end. She disappeared into Darkness. Larxene was the second member to be eliminated.

'''XIII. Roxas''' - Arguably the only surviving member. Roxas permanently sealed himself within Sora just before the final battle with Xemnas, willingly giving up his physical existence. Although he is not gone, he was the twelfth member to "fall", thirteenth if Xion is counted.

'''XIV. Xion''' - While technically not an official member, she was still part of the Organization for a while. She was defeated by Roxas while battling him and then faded away to join with Sora. If she was considered a member, she would be the sixth to be defeated.

True Organization XIII
The True Organization XIII (真のXIII機関), also known as the Thirteen Seekers of Darkness (13人の闇の探求者) is a group consisting of thirteen different incarnations of Master Xehanort that debuts in Kingdom Hearts 3D: Dream Drop Distance. The actual purpose of the original Organization XIII was to host a fragment of Xehanort's heart in each member, turning them into his vessels. However, many of the original members turned out to be either too weak or traitorous, leaving only Xigbar and Saïx as worthy members. However, Master Xehanort managed to gather 12 vessels of himself thanks to Young Xehanort and Ansem, Seeker of Darkness, though he failed to make Sora the last one, and fled with an incomplete Organization to put his plan in practice. Yen Sid has already told Mickey about this in Signs of What's Next, when he said that one Keyblade Master alone will not be enough to face what is "not a single Xehanort".

Members
I. Master Xehanort - The original incarnation of Xehanort, a Keyblade Master who masterminded behind all the chaos and destruction that has besieged the Realm of Light thus far. He commands the Darkness, and wields his Keyblade on the few occasions he has been forced into combat.

II. Xemnas - Master Xehanort's Nobody. He created the original Organization XIII, however Sora and Riku, as well as internal strife quickly reduced their numbers. Sora and Riku destroyed him, causing him to fade away into nothingness, however due to Young Xehanort's meddling in time he has returned. He wields Nothingness, as well as a pair of Ethereal Blades known as Interdiction.

'''III. Ansem''' - Master Xehanort's Heartless. His missions were to both enable Xehanort's younger self to travel through time and oversee Maleficent gather the seven Princesses of Heart. Though he possessed Riku to regain physical form to go after Kingdom Hearts, Sora put an end to his plans. His Darkness lingered within Riku until the boy put an end to him, however he has been revived due to Young Xehanort's travels through time. He wields Darkness, and lacks a weapon, instead fighting with his Guardian symbiote once wielded by Terra-Xehanort.

'''IV. Xigbar''' - Originally Braig, a mercenary hired by Master Xehanort to help speed Terra's descent into Darkness, Xigbar was Xemnas's right hand in the original Organization XIII, however Sora put an end to him. Despite this he has returned due to Young Xehanort's interference. He reveals that he joined Xehanort so he could claim the power of the Keyblade as his own. He wields Space, and his weapons are a pair of Arrowguns, the Sharpshooters.

'''V - VI. Unknown'''

'''VII. Saïx''' - The Nobody of Isa, and Xemnas' second in command of the old Organization XIII. His reasons for becoming a member of the True Organization XIII are unknown. Sora ended him once before, however due to Young Xehanort he has returned. He wields the Moon element, and his weapon is a Claymore called the Lunatic.

VIII - XI Unknown

'''XII. Young Xehanort''' - A younger version of the original Xehanort. Meeting Ansem, Xehanort was enable to journey through time as an insurance plan incase he and Xemnas failed on their own. It is due to him that the True Organization XIII was able to rise. He wields Darkness and Time, and fights with an unnamed pair of Ethereal Blades and a Keyblade.

'''XIII. Unknown '''

Possible Members

 * Terra-Xehanort - Xehanort mentions that one of the possible Seven Lights are on his side, this may mean that Terra-Xehanort is one of the Seekers of Darkness.
 * Vanitas - In La Cité des Cloches, Young Xehanort appears with what seems to be Vanitas' heart inside of him. An apparition of Vanitas manifests beside him and the two speak to Sora in tandem. It is possible that Vanitas will somehow be revived, seeing as how his heart is so close to Xehanort's.

Theme

 * In the album Drammatica, the song The 13th Anthology features the Organization's theme as well as most of their battle music.
 * The Piano Collections Kingdom Hearts also feature the theme of Organization XIII.

Trivia

 * After Sora obtains the password for the DTD, the Journal entries for the Kingdom Hearts: Chain of Memories Organization XIII members are obtained. It is unknown why this is, as Sora had lost his memories of them, although it is believed that this information was obtained from Ansem's computer in Hollow Bastion. In Kingdom Hearts II Final Mix, this is changed: the Journal entries for the Kingdom Hearts: Chain of Memories Organization XIII members are obtained only after defeating their respective Absent Silhouettes, before or after the Battle of the 1000 Heartless.
 * At least eight of the Organization members were citizens of Radiant Garden, and Sora released his heart, creating Roxas, within Hollow Bastion.
 * Despite how often the members fight among each other, only Axel and Roxas actually kill another member, with Axel killing Vexen and Roxas killing Xion.
 * As of the events of Dream Drop Distance, the names of all but four Organization members' original selves have been revealed: Demyx, Luxord, Marluxia, and Larxene. These four are also the only ones whose world of origin is unknown.