Blue Fairies
Blue Fairies have the ability to change animated wooden puppets into the thing they are supposed to represent. Pinocchio for example was transformed into a snotty kid by the Blue Fairy with Turquoise Wings. She apparently did it as a favour the toy's creator and to also show that true faith requires a path of cruelty and tears first.
This makes the Blue Fairy one of the 'good Fairies'. Others members of the species are far more dangerous and like to torture humans for fun. Otherwise Blue Fairies go around the world offering assistance and giving out prizes. This has led them to be confused with the Tooth Fairies who only offer their services if you leave your teeth under a pillow.
Hunted[edit]
Humans find all fairies (well, nearly all) an exquisite delicacy to enjoy. Blue Fairies are said to be the most pleasant to chew on, once you have removed the wings and clothing. Witches often hunt Fairies as ingredients for their cauldrons.
Special powers?[edit]
If you can refrain from eating them, the next best thing to do with a Blue Fairy is to cage it and try and persuade the animal to grant you three wishes. Remember to be very precise in what you want. Generalities like 'give me gold now' rarely work as all fairies including the blue ones can give you something which then turns to mist half an hour later. By that time the Blue Fairy has taken wing and now hides in the bushes.