I finished the game today and the story line is awesome. Im going to keep this review short to avoid spoilers.
You play as roxas in this game between the time sora was getting his memories restored. There are 3 main people in this game sora axel and xion. Xion is number XIV and a new character.
I would have made this game 10 but i thought that some of the parts were very boring, i would only play this game for the story because the story is worth it alone. You play as roxas and go on missions with members of the orginization or alone, and there is also a nifty multiplayer mode. There is also a mission mode where you can play as many different characters ( xemnas xaldin roxas axel xion luxaeus riku donald goofy luxord marluxia demyx xaldin vexus larxene saix and lexion.
There is also in story mode various twists and turns that you would have never suspected