each level == 3 rooms :
1 virtual
1 up
1 down

each level would require its own, assigned virtual idea.
no random picks otherwise you can't have :
each level containing a hidden 'key' for the level below
ie : a shovel

could have one main file that chose npc files based on
depth of dungeon while at same time rolling for a random
virtual type per level?  each virt type would be based
not only on kind of layout but also which quest. (this
would create redundant virtual files of similar layout 
but allow for varying key items and break monotony.)
