Solutions to war, famine, disease and societal collapse are not easily happened upon. For Celestia and Luna, the solution was a mystery for eons, until their top six battle mages forged a plan from their very essence. To unite their absolute individual powers into one worthy host. One who could put an end to the horrors plaguing the budding nation of Equestria.
Only one pony was ever worthy. His deeds and heroism ultimately culled evil and hatred from Equestria and allowed peace to reign. After this achievement, the power vanished of its own accord upon the natural death of its wielder.
However, it seems that something in the shadows has provoked the lost power's return in the form of a new carrier, and she's going to find out her true destiny through a series of literal trials by fire.
(Updated on 3/1/2019, I'm ashamed that its been almost 5 years since my last chapter update...)
This is my take on the origin of "Super Rainbow Dash." Shout out to the creator of Super Rainbow Dash, Super Klonoa. My apologies for not finding out who you were sooner!
Thanks to unexpectedly high ratings, this story has been moved from an experimental work to a full production. Edited by the Awesome Amazing Regular... uh.. "Solid" SolidFire.