I actually did this a while ago. We were asked in class to do a few perspective drawings of buildings/structures. The first of which I did was Skull Castle from MegaMan Classic.

Now, mind you, I have no idea which game this was from. I did it from memory so it's probably not any of the official ones and the perspective is probably wrong, but it is kinda cool. Lol. There's another one coming too from the X series.