There's long been rumors as to how, exactly, rainbows are made in Equestria. While a great amount of Pegasi ponies are employed in the Rainbow department of the weather factory, almost all of them do the low-end work. What's know is that great streams of Spectra, the individual colours of the rainbow, flow through large grates and into vast vats. From there, workers carefully and equally mix the spectra into the coagulated rainbow pools that dot and run through the factory and surrounding city. Next, that mixture is pumped to the floor below, where other employees atomize it and store it until the active weather Pegasi deploy it in field.
However, no one knows how individual Spectra is made. Supplies are never seen being brought in, leaving not even a clue what goes into a rainbow. Tourists, when visiting the factory, are treated to an extremely foreboding and plain wall, with massive solid doors baring entry to anypony at any time. While most of the facility's various signs and architecture is bubbly and welcoming, the Rainbow Factory's upper floor was protected by harsh imagery of potential hazards and death, and the cloud wall was made not out of the clean white of the rest of the city, but of a black, quietly thundering fog.
To become an employee of the upper Rainbow Factory mean sacrificing any life outside those black walls. Workers are sworn to secrecy and forbidden from leaving, and live inside the facility itself. Those few who ever managed to make it out not in a body bag were twisted and disturbed, too damaged to ever bring themselves to talk about it. A lot of theories were proposed; Dark magic from captured unicorns, chemicals and environmental hazards that no sane pony would tolerate, and even thoughts of another unknown sister of Celestia's, destined to create the Spectra instead of raise a sun or moon.
None of them could be farther than the truth.
(Sorry short chapter)
