Once you complete the game you have the opportunity to go through the Dragon Lair Cave. Once you finish that, you can go through the Corridor Of Distortion. Then, you will fight your father. After that, you will fight Lenneth Valkyrie, the main character of Valkyrie Profile. After you fight and recruit her, you will face an interesting character whose name is Lezard. This is Lezard Valeth from Valkyrie Profile. After that, you will face Gabriel Celeste, another hidden Boss from Valkyrie Profile. The final and toughest Boss, the Ethereal Queen, also seems to be modeled after Iseria Queen, also from Valkyrie Profile. Note: All of these characters, with the possible exception of Lezard, also appear in Star Ocean: Til The End Of Time.