I have always seen Dracula's Castle as being a entity ever since the first Castlevania. Why wouldn't it be? The castle certainly has its own character and personality. In the very least the concept is just great story telling. Alucard, who had "most likely" lived there at one time, indicates that the castle is indeed "A creature of Chaos." Personally, I see the whole saga as being ultimately about Castlevania itself (hence the games title) and everything else simply evolves around it. I would love to see more on the subject in the sagas near future. -Amber