Thanks for taking the time to say such an insightful comment. And yeah, the Cube was the most time-consuming element. That and getting the terrain together with the Cube being in the sky in my mind as I rendered it.
The Borg not only can gobble up entire cities out of the ground, but they did--there was mention in some other Next Generation episode that somebody had been running along the Federation-Romulan border, yanking entire colonies out of the ground. Nobody outright mentions it in an episode, but I read an interview of one Trek writer who confirmed that it was indeed the Borg.
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