Recent news has come to light regarding the next 3 Kingdom Hearts games. Kingdom Hearts 3 has been announced as a seperate project, but there is no further information on whether it will be centered around Sora, Riku and Kiari or the new characters Zen, Azure and Terra.
HOWEVER:
The next three games are not the already aclaimed title Kingdom Hearts 3. In fact they are more of a backstory so bear with me as i atempt to explain...

KINGDOM HEARTS: BIRTH BY SLEEP (PSP)
This follows the story of the Knights seen in the ending to Kingdom Hearts 2. Zen (the Roxas look alike) Azure and the leader, whom seems to be the main playable character, Terra. According to Nomura, this will deal with the original 'true' keyblade master and explain a bit more about the keyblade war.

KINGDOM HEARTS: 358/2 DAYS (DS)
This time, the DS version of the game centres around Roxas' time in Organization 13, whilst Sora is asleep. Playable characters include Roxas, Axel, Siax and other members of the Organisation. The game has been nicknamed Chain of Memories 2, but i hope it wont use the same card system.

The other game is purely for the Mobile Phone and not really worth commenting on. It involves a series of short adventures of Soras that have nothing to do with the actual story.

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