I have been playing the crap out of Halo 4 (Help I think I'm addicted ) and in doing such, just like any responsible Brony would. I related ponies to it! How? Well, for those who are halo fans recently, shit has hit the fan in the halo universe, with Cortana basically becoming a galaxy wide Skynet, more and more Forerunner secrets becoming unearthed, but I'm really just rambling. What I did was sit down and contemplate about how..

A: Celestia and Luna are basically immortal (I guess Twily and Cadence are too, but this isn't about them)
B: The fact that they control the Sun and Moon and are the only ones who can pass said control onto another
C: All of the mythical and magical things that happen on a day to day basis.

This all got me thinking. What if Luna and Celestia are the remains of Forerunners who watched over this world, this shield world of Equestria (or Equus, whatever tickles your fancy)? What if they indexed the ancient Equestrian's ad other species on this planet behind The Librarian's back because they grew fond of the creatures that see them as gods or rulers or whatever. One thing that didn't stack up in my comparisons were magic, then I though about how they use hard-light for architecture, weapons, and general functionality. What if they somehow put the ability to project hard-light into unicorns. Pegasi, well they can just fly (not gonna try to debunk that) and earth ponies are just regular talking horses.

As for the sun and the Moon, well these two sisters were in charge of creating sustainable biospheres for the shield worlds like requiem and others. Celestia made the artificial star, and Luna fabricated the pseudo moon(s). For Twilight and Cadence, I guess they would have their own "Mantel of responsibility". Like how only true compassionate, innovative, and headstrong ponies can uphold the mantel. That would most likely be where alicorn transcendence comes from. Honestly, I can go on for hours, but I feel I've talked your ears off enough. P Lease leave an idea or comment below.