A final edit, which I completed after the challenge had passed, but had been part of the original shortlist.
The render I submitted for the challenge. I had numerous lighting setups prepared, and committed to this during the terminal stages of the challenge period.
The original concept. It looked phenomenal in the viewport, but the lighting did not bring out much detail in the final 4k render.
The clay renders that correspond to the scenes. A really handy tool for a real-time engine to have, and one that you can easily enable in the viewport in D5 Render.