Saddle Rager is part of the fictional comic book superhero team the Power Ponies appearing in "My Little Pony: Friendship is Magic". A member of the Power Ponies who can turn into a hulking monster with tremendous strength when she loses her temper. She has powers similar to Marvel Comic's Hulk.
My Little Pony Annual 2014
In the 2014 Annual of the My Little Pony comic book, a full Power Ponies adventure is shown where Saddle Rager uses her powers.