There is, they say, a wandering, cloud island, that is home to clowns. These are no mere performers but the thing the mummers ape, fey and changeable beings not of this world.
Where the cloud island passes in it's maundering way, the clowns come down among normal folk, dropping from the sky under motley umbrellas, or sliding down shafts of light. They put on carnivals, perform farces, and throw out candies. After they have gone, people are sometimes found missing, particularly children.
Sometimes when the island passes, the clowns don't come down but instead drop candies of preternatural flavors and small items imbued with magic: a hand mirror, a short sword, a jar of skin cream, a pack of gum. There are rumors that these come in trade--or are perhaps stolen--from the Moon. There are tales spun of daring thieves sneaking on to the cloud island to rob the clowns' treasure stores, but as far as is known, these are just stories.
Other tales purport to come from people who have visited the cloud island and returned. These seldom mention treasure stores, but do describe colorful tents scattered among cyclopean stone ruins (that may predate the clowns) and the rare tree, strewn with mists and carnival lights. The anarchic clowns careen between merriment and slumber. No clown ever seems to die, no matter what sort of violence is done to them.