As I viewed the pageant of mural history I had approached very closely to the end of the low-ceiled hall, and was aware of a gate through which came all of the illuminating phosphorescence. Creeping up to it, I cried aloud in transcendent amazement at what lay beyond; for instead of other and brighter chambers there was only an illimitable void of uniform radiance, such one might fancy when gazing down from the peak of Mount Everest upon a sea of sunlit mist. Behind me was a passage so cramped that I could not stand upright in it; before me was an infinity of subterranean effulgence.
-The Nameless City ; H. P. Lovecraft
TLDR: Even the quickest Pegasus might feel trapped in the sky, and where then might they escape to?
This was fun as all heck, and finished surprisingly quickly! Only two hours on and off.