Replica

Replicas (レプリカ) are artificial copies of people. They were created by Organization XIII and first appear in Kingdom Hearts Chain of Memories.

Kingdom Hearts Chain of Memories
The Replica Program was one of the experiments being carried out in Castle Oblivion.

The public purpose of the Program was to find a way to replicate a Keyblade wielder's power by inserting a piece of their memory into a blank replica. A vessel deemed unworthy of the program was instead given Riku's data to create the Riku Replica. Said replicas show the capacity to grow in strength by absorbing other lifeforms.

The Replica Program ceased with the demise of Vexen.

Kingdom Hearts 358/2 Days
With Vexen's demise, the Replica Program is rendered inoperable. The only success to come from it was Xion, the only replica from the program to develop into its own person. Even if a replica gains free will, they are still susceptible to reprogramming; they can be made to follow a specific order or have their appearance modified, even changing their original gender.

As previously stated, replicas can naturally grow stronger, drain the vitality of others or be given an external power up. Xion unknowingly takes Roxas's energy and uses the Organization XIII Devices to obtain new forms. However, the method in which the replica is fashioned can have unforeseen side-effects. Although Xion's true form is meant to resemble Sora's appearance, Xion's appearance is somewhat unstable as result of her being crafted imperfectly from Sora's memories. Thus, Xion's appearance differs depending on who sees her.

Kingdom Hearts III
Saïx approaches Even and convinces him to become a Nobody once again. With Vexen's research, the real Organization XIII are able to create replica bodies for the hearts of their time-traveling members, allowing them to stay anchored in the present time. Wishing to atone, Vexen has Demyx deliver a blank replica to Ienzo in order to provide Roxas with a body separate from Sora. Likewise, once Dark Riku's heart is forced out of his vessel, the now blank replica is used to give Naminé a body.

In Scala ad Caelum, twelve replicas modeled after the members of the real Organization XIII fought Sora, Donald, and Goofy before Xehanort himself confronted the trio.

Nature
Replicas are blank figures akin to mannequins that take the form of whatever heart or data of a heart is placed inside of it. They have the same skills as the individuals used to create them. They also have the unique ability to absorb other individuals. The Riku Replica was created using data Vexen collected from fighting Riku, while Xemnas used Sora's memories to make Xion, an imperfect replica of Roxas. In the manga, Vexen fashioned 44 replicas of himself.

Over time, replicas like the Riku Replica and Xion formed identities, and therefore "hearts", of their own, becoming their own people.

In Kingdom Hearts III, the real Organization XIII re-recruits Vexen to continue the Replica Program. As Vexen explains, these newer replicas become real people once given hearts, unlike previous models, which were more akin to Nobodies.

List of Replicas

 * Innate Replicas

Notes and references
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