tlowr, I told you I'd post instructions on how to build your Hidden-City easier using WorldEdit, so here it is: (with some of the commands just to make it easier to understand)
First off, I'm not done with it yet, so I'll only put what I've done so far.
I found a semi-flat chunk of land and selected roughly a 100x100x100 chunk
//replace 0
Then I went to the middle of the cleared area, (make sure you're in the DEAD CENTER) and dug about 7 blocks down
//sphere stone 75
//unstuck
//br sphere stone 7 (<----- that's not a typo, I'll tell you how I did that if you want me to)
Then I just brushed all over the stone sphere and at the base of it to make it blend into the surrounding land
//smooth 5
I smoothed everything out...
Remember what I said that the sphere had to be in the middle of the area you selected? This is why:
//overlay 2 (<--- block ID)
If you didn't center your sphere perfectly, it won't be overlayed in certain parts and you'll have to make a new selection to apply the overlay to the parts that didn't get overlayed.
I also smoothed the areas around the part where I replaced everything to make it look natural.
Sorry if there's any typos in the code!
More to come once I start hollowing it out...
Also, could you post the video so I have it for reference?