1988: Brush 'n' Grow Ponies
Yellow earth pony with red, green, pale pink and blue mane and tail, red and blue mirror tied with a blue bow symbol.
Pretty Vision. Unfortunately, mine isn't really one...but hopefully the above picture gives enough of an idea to be going on with. Like many Brush 'n' Grow Ponies, she features that pale pink streak that often fades to white - but any with white streaks are not variations.
In the comics, Pretty Vision's special magic related to her magic mirror (predictable much?) It was said that, if she or a friend looked into her magical mirror, light would shine out of it and style her hair with pretty ribbons. (Well, okay, I guess that's not quite so predictable...)
Unlike Twisty Tail, she did not have an alternate version in the North American release.