missions. Xion eventually discovers her true identity as an artificial human "replica" created from Sora's memories to duplicate Roxas' powers, which forces her to sacrifice her existence and all memories related to her in order to protect her friends. She is later revived as the final member of Xehanort's thirteen "seekers of darkness" before regaining her original memories and rejoining her friends. Xion is voiced by Risa Uchida in Japanese; in English, Xion is voiced by Alyson Stoner in 358/2 Days and Kingdom Hearts III, and by Hayden Panettiere in Birth by Sleep and Dream Drop Distance. Riku Replica is a replica created by Vexen from the real Riku's combat data, first appearing as an antagonist in Chain of Memories. Initially appearing to be the real Riku under the influence of darkness, his true nature is revealed after he battles Sora to protect Naminé, who previously altered his memories so that he believed himself to be real as part of Marluxia's plan to manipulate Sora. The game's "Reverse/Rebirth" story mode depicts Riku's confrontations with his replica, who is eventually destroyed in a fight meant to prove his own right to exist after discovering his origins. In Kingdom Hearts III, Riku finds the replica's heart in the realm of darkness and gives it refuge within his own heart. A past version of the replica called "Dark Riku" also appears in the game as a member of the real Organization XIII, masquerading as the real Riku's younger self. After Dark Riku is defeated, Riku Replica sacrifices himself to extract Dark Riku's heart from its vessel, which he provides for Naminé. Ansem the Wise is the former sage king of Radiant Garden, first appearing in the "Reverse/Rebirth" storyline of Chain of Memories as a bandaged figure known as . His true identity is uncovered in Kingdom Hearts II, simultaneously revealing the similarly named antagonist to be an impostor. Nine years prior to the first game's events, Ansem studies the darkness in people's hearts for the benefit of his world after taking an amnesic Terra-Xehanort in. After meeting with King Mickey and learning his research may be connected to a crisis happening in other worlds, Ansem ceases his experiments. However, Xehanort secretly continues the experiments under Ansem's name alongside Ansem's other pupils—Braig, Dilan, Even, Aeleus, and Ienzo—who exile Ansem to a world of nothingness and form Organization XIII. Ansem disguises himself as DiZ, an