They are the Founders of Equestria. Clover the Clever was Starswirl the Bearded's apprentice and she created the Fire of Freindship to defeat the Windagoes the winter spirits who feeds fighting and hatred
Clover the Clever... I don't suppose your take on her was inspired by one Pony named Fae Prism ([link]), was she? xD They look really similar and I actually thought I was looking at Fae before realizing what this collection was meant to represent.