This Soundtrack is really powerful and when the word powerful came to my head i thought princess celestia ( i think it's a good match :)

Pony - Celestia 

Soundtrack - http://www.youtube.com/watch?v=rY07_dX3F88

ART 
http://browse.deviantart.com/?qh=&section=&q=princess+Celestia

princess Celestia belongs to HASBRO X3

soundtrak belongs to dreamworks animation skg

(I do not own anything, I made this just for fun)