Fawn and the Mysterious Trickster is the fifteenth Disney Fairies chapter book published by Random House.
In this book, Fawn loves practical jokes. So when her friend Beck plays a trick that scares the pixie dust off her, Fawn is impressed. She gets Beck back, and in the blink of a dragonfly's eye, the two fairies in an all-out practical joke battle! Prank follows prank, until one night someone turns all the furniture in Beck's room upside down. And it wasn't Fawn! But if Fawn didn't do it ... and Beck didn't do it ... then who did? Is there another trickster in the Home Tree?
The two fairies eventually set up a trap to capture whomever has been pranking them- much to their surprise, the culprit is Fawn herself! It turns out that the animal-talent loves pranking so much, that she's been doing so in her sleep! The two fairies share a laugh over the end result.