On the main DVD menu screen, when play is highlighted, press up. You will highlight one of the crystals. Press enter, and it will take you to a screen with a bunch of different character's faces. Press enter on any of them, it will give you a soundbite from that character. Also, you can highlight the two crystals on the bottom of that page that are on either side of the main menu option that will give you two other soundbites. On the main menu screen, you can't seem to highlight the other crystal. I don't know why.
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