The prequel to the popular series Kingdom Hearts. It's only playable on PSP. It features three main protagonists: Terra, Aqua, and Ven, who are each keyblade bearers in training.
Tetsuya Nomura, the director/character designer for the series, stated that Birth By Sleep will answer a lot of questions that were left unanswered in the previous games.
The game is currently available in the United States. It has received both positive and negative reviews.
The suggested play order for Birth By Sleep is as follows:
Terra, Ven, then Aqua.
Xehanort is the main antagonistic in Birth By Sleep.