Dance 'n Prance Ponies were released in Year 7 of the My Little Pony line and featured ponies that would "dance and prance" with spinning tails. Each pony had a wind-up flower attachment on its chest that would make its tail spin when wound. The spinning vibration would make the pony dance.
The Dance 'n Prance Ponies came with fancy hair and jewelry accessories like hair clips with colorful hair extensions, mesh ribbons, barrettes, and clip earrings.
Like any wind-up toy, these spinning mechanisms were often overwound, so it's hard to find these ponies in good working condition. It's common for the tail to spin just once or twice before stopping or for it to spin quickly but without enough vibration to make the pony dance.