She is one of the main characters in My Little Pony.
Buttercup is a character from The Powerpuff Girls, and not from My Little Pony.
Currently there are only two: Equestria Girls and Rainbow Rocks.
My Little Pony Equestria Girls - Rainbow Rocks - 2014 was released on: USA: 2014 Australia: 26 December 2014 New Zealand: 26 December 2014
Yes, the My Little Pony Friendship is magic episode Twilight's kingdom is involved in the rainbow power.
Probably not. It has been said by the production team of Equestria Girls that Equestria Girls was meant to be a standalone, and not be connected to the TV show My Little Pony: Friendship is Magic.
The Crystal Empire is the Rainbow Kingdom in your Little Pony Friendship is Magic.
Yes. The Dazzlings are sirens.
yes
No. Rainbow Factory is not licensed My Little Pony material. It is a horror genre fanfiction that was published online.
Yes, the Twilight's kingdom from My Little Pony Friendship is Magic is the Rainbow Kingdom.
I think it's about when twilight sparkle comes back with her crown.
So far it has not been mentioned as to whether or not he will appear.