Kingdom Hearts Final Mix is a version of Kingdom Hearts only released to Japanese retailers. It gets released soon after the original Kingdom Hearts release and boasts new features and cutscenes not seen in the original version. For example, in the North American and European version, you had the option to fight Sephiroth, however the original Japanese release has no such optionThe creators and staff come back and add extra stuff that was included in the North American and European versions, and a little etxra to the Japanese version, hence, "Final Mix." The extras in Final Mix are the same as the North American and European versions except more extras have been added.

Features present are a new boxart, added new optional bosses, Sephiroth, Kurt Zisa and the Phantom. A couple of new cutscenes, new breeds of Heartless, two new Keyblades, One Winged Angel and Diamond Dust and another optional boss fight against a cloaked Organization Member.