Played on the DS, the game revolves around the origins of Roxas. As the first seven days of his life is unknown, he is recruited by Organization XIII due to his special ability to weild a keyblade. Unlike other members, only when Roxas defeats a heartless will the the heart go into contribution of Kingdom Hearts. It is made clear that the Organization XIII wants Kingdom Hearts completed in order to gain their own hearts. As nobodies they are unable to have any feelings due to a lack of a heart, and mock Roxas on several occasions when he feels emotion saying he is only "remembering an emotion." Later, a new member is introduced known as Xion. Unlike the other members, the player learns that Xion is not a nobody, but a puppet. Xion is also able to weild the keyblade, which made her extremely useful to the Organization. However, the Organization looks down upon her as merely a puppet and does not recognize her as an official fourteenth member. It is later learned that Xion is created by Sora's memories which explains her unnusual facial resemblance of Kairi. Xion strays from the Organization's agenda and sides with Riku, who has been dressing as an Organization XIII member and was refered to as "the imposter." Riku reveals to Xion that she is an important piece required to wake up Sora from his year-long sleep. Xion makes the choice to give herself up to awaken Sora. In the end of the game Xion fights Roxas at Twilight Town, but using her powers she made the illusion the two were battling in other worlds such as Halloween Town and the Cave of Wonders (Alladin). After defeating Xion in several forms, Roxas emerge victorious. However, since the two had a strong friendship throughout the game, Roxas is saddened by her defeat. Xion is wasting away, returning to Sora's memories. At this moment Roxas memories are damaged, and his memories are fading. He looks at Xion and mutters, "Who are you... again?" Xion finally dies and her body dissapears, returning to Sora's memories. Roxas is filled with rage and vengence and looks to end Organization XIII. He goes back to The World That Never Was in attempts to defeat the XIII and stop them from getting Kingdom Hearts. However, he encounters Riku who tries to stop him and warns him he will be defeated. Riku is unaware of how Roxas has a keyblade. The two fight, despite this being the last boss battle, fighting Xion was probably much more difficult. At the end of the game, Roxas wake up in Twilight Town. Roxas's memories have completed faded, and he believes he is an average boy with strange dreams (which are really his hidden memories). The end of 358/2 Days is the beggining of Kingdom Hearts 2.