The Gold Dragon Castle is attached to the top of the City of White Nights. There is a temporary save flag as well as a healing circle at the bottom of the tower. At the top of the tower, you will find Ridley communing with Quasar, the Gold Dragon. No matter which path you have taken, you will stop the communion, then end up fighting Lucian, who is revealed to be Aphelion, the Silver Dragon, who wants to rule the whole of the world without the other Dragons getting in his way. The dialogue and eventual ending scenes differ for each path, but Aphelion dies either way.