Kingdom Hearts 2 was released December 22, 2005 in Japan and KH2 Final Mix+ was released March 29, 2007 as an only Japanese released game. They had done the same with the original Kingdom Hearts game but they released the Final Mix version at the end of the same year. Instead of just the Kingdom hearts 2 game packed full of extras it came with a bonus disc of the re edited version of Chain of Memories for the PS2. That made the import rate jump quite a bit I'm sure.
The Final Mix version of the game has a bunch of extras not in the original releases and with additional cutscenes. They added 7+ new boss battles which are the shadows of the organization members you encountered while in Castle Oblivion during Chain or Memories and Enigmatic Soldier from the secret trailer at the end. There are 10+ new cutscenes that add to the story and 2 additional side quests. One of the side quests is fighting a bunch of Organization 13 mushrooms and the other is through out the whole game you collect pieces of pictures and put them together in your journal. They added a theaterical mode where you can watch the cutscenes seperatley from the rest of the game in japanese and english.
You have to have everything done in the game to watch them in english I believe and you can watch them in japanese after you beat the game in any difficulty and without everything done. They added an additional difficulty now instead of Beginner, Normal and Hard there is now Critical mode. There are new explorable areas now as well the Cave of remembrance and the garden of assemblage. Stat and color change in some enemies.
A new limit form (I think it's called Brave form), new drive guage max (now it's 9), new synthesis items, accessories, and Sora gets two new weapons. One is "Acrossing Two" and the other is "Proof of Victory". They also decided to change Sora, Donald and Goofy's costumes in Christmas Town. Instead of them being dressed in their Halloween attire as before they are now full of Christmas cheer instead, Sora is adoreable in a santa suit, Donald as a toy soldier and Goofy as a reindeer.
It was worth the money with all those extras even if I can't understand the new cutscenes right now as it's all in japanese subtitles with no sound. Of course with all these pros come cons as hard as that is for me to say but there were a few "glitches" they decided to take out. After you beat the Pride Lands you could go back and find a bunch of flying heartless after you beat them all you could leave go back and they would be back everytime. That was the easiest way by far to get to level 99 and now since they took it out it's much harder to level.
When leveling up Master Form you could go to Land of Dragons at the Check Point and destroy exploding carts that gave you drive orbs. You collected them all, left the area, went back and the carts were back. So it's much harder to level up Master now too seeing as how drive orbs can only be found in Land of Dragons I believe. Needless to say I haven't had the patience to level up my forms yet.
I don't regret getting it though since I do need kind of lesson on patience and I love the all the additionals. I'm still looking to get my hands on Kingdom Hearts Final Mix, most is pretty much the same as the American release except at the end in Hollow Bastion you get to beat an unknown Organization Member who just happens to be Xemnas the leader of Organization 13.