According to the Dragon Quest IX DS case, the game only has one save slot . DQIX producer Ryutaro Ichimuar explains why. “Because the amount of freedom we give players is huge,” says Ichimura, “the data that needs to be saved is enormous.” Thus, it was difficult for Square Enix to create a save file and squeeze in a back-up save file in case the DS’s battery dies suddenly. If a back-up data save file wasn’t created, players could lose

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Dragon Quest IX’s One Save Data Slot Explained! [Square Enix]