He didn't leave anything for you to tell by.
D appears to be some sort of torture chamber. Well, certainly the long wooden impliment that is its only 'furnishing' appears designed to hurt people that are trapped in it, certainly.
Roan, you come into X
Uh-oh...
This is a large computer bankwith a Bond-villian sized screen on the far side looking over all. All the screens are blank, and little rivvulets of blue electriacal energy are shooting along the main screen and the computers.
The 'uh-oh', though, was the furnishings. This whole place is decked out in great flowing banners and decoarations- inalid with the unmistakable symbols of the Sith.