What is Organization XIII? Well if you have played Kingdom Hearts: Chain Of Memories you will have undoubtedly met a group of people that called themselves the Organization. They are being called the Organization XIII now, simple as that. XIII symbolizing the number of members in the Organization - 13. Each member has a number - the numbers being based on the order in which they joined, not necessarily how important to the plot or how powerful they are. Organization XIII are all advanced forms of Nobodies, who kept human form when they lost their heart and became a Nobody because they had a very strong heart. At least some of this group of people were at a place known as Castle Oblivion in "Kingdom Hearts: Chain of Memories" (Axel, Marluxia, Larxene, Vexen, Lexaeus, Zexion). They all wear long black cloaks, and that is the easiest way to identify them. Certain members were trying to bring both Sora and Riku under their control during Chain of Memories for their own purposes. Organization XIII is not without its internal disputes. In Kingdom Hearts: Chain of Memories Marluxia and Larxene try to take control of the Organization by manipulating Sora, thus obtaining the power of the Keyblade. Lexaeus, being rivals with Marluxia, tries to bring Riku under his control in order to contend with Marluxia's bid for power. Marluxia also blackmails Vexen making him fight Sora on his own, threatening to inform the Superior of a recent failure. Axel eventually kills Vexen, orders Zexion's death, and allows for the demise of both Marluxia and Larxene.
In Kingdom Hearts: 358/2 Days, we learn about a new 14th member (XIV) named Xion. The orignal purpose was to divide Master Xehanort's heart among thirteen vessels, but most of the members were inadequate.
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