Replica Program

The Replica Program was a planned series of experiments conducted by Vexen under Xemnas's orders, with the apparent help of Naminé. He attempted to make Replicas of Keyblade wielders Sora and Riku in the event that the original Sora proved to be useless to his plans for Kingdom Hearts. The first replica created by the program was Xion. However, after Xion's defection and her death by Roxas, Xemnas discontinued the program. In the Secret Reports it mentions another inferior numberless replica that was taken to Castle Oblivion. The Secret Reports in Kingdom Hearts 358/2 Days also reveal the existence of other unused replicas.

Xion
Xion is created by Vexen out of Sora's memories. She holds these memories which will stop Sora from being able to awaken from his slumber. Xion, being made out of Sora's memories, can wield a Keyblade, something Organization XIII wanted. This will make it so Organization XIII has two among their ranks that can wield the Keyblade and collect hearts to form Kingdom Hearts. She is seen by some as only a puppet, while only Roxas and Axel calls her a friend. She is defeated and absorbed by Roxas, and the program is stopped shortly after her defeat.

Riku Replica
The Riku Replica is created shortly after Xion's creation by Vexen. He creates this replica after sampling the real Riku's memories. Vexen uses this replica to fight both Sora and Riku. The Riku Replica always knows he is the fake one, but always fights to get rid of Riku, what the Organization wanted. He met his demise by Riku, and is swallowed by the darkness after his defeat.

Notes and References
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