In this game you play as Roxas. The game starts at day 255, and then goes back to day 7 after. On day 7, a new member is in the organization, number 14....Xion. Throughout, the game, she befriends Roxas and Axel. She meets many people during the game, including Riku. She meets Riku twice. At Destiny Islands and at Beast's Castle, where Riku calls Xion's keyblade a fake, upsetting Xion. Riku and Xion have a battle, with Riku as the winner. He walks away saying,"Here's some friendly advice, leave the organization soon." Later in the game, Xion disappears, only to be found by Axel in front of the Twilight Mansion. Then, Axel says," No matter where you go, I'll always bring you back."

MAJOR SPOILER!!!!!!!!!
Xion is capable of taking forms of various people in Sora's memory. How is she able to do this? Well, she is an imperfect replica of Sora created from his leaked memories. So aparently, Sora remembers a little bit about our speedy hero Ventus, allowing Xion to transforming into Ven during her battle with Xigbar.
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