I think we all are familiar with the mythological figure known as Puck because of his debut appearance in the famous play Midsummer Night's Dream by William Shakespeare. I did some digging on the character and in general Puck could refer to any fairy, sprite, pixie or hobgoblin that is considered mischievous, a trickster or prankster.
In English folklore, Puck is mythological fairy or mischievous nature spirte. Puck could come from the Old English term 'puca'. It's not really clear where the origin of the word came from but the word can be traced back to Old Norse puki, Old Swedish puke, Icelandic puki. In the Celtic world ( Welsh pwca, Irish puca).
He is seen as a half-tamed woodland spirte who leads folk astray with echoes and lights at night in the woodlands. In some tales he is known to come into the farmsteads and sours the milk while in the churn.
In Middle English the word Puck simply meant 'demon'. The term also known as Pouk was used as a typical term for the devil and Hell was once called 'Pouk's Pinfold'. In Elizabethan lore he was a mischievous brownie like fairy who was also called Robin Goodfellow or a Hobgoblin.
In the Welsh mythology he was called Pwca, which was a queer little figure, long and grotesque, looking something like a chicken half out of it's shell. He would lead travels with a lantern into the night. When he lead them to a cliff side he would then blow out his lantern and they would fall to their death.
In Irish mythology he was called a Phouka who sometimes appeared as a horse. People would be tricked to jump on him then he would lead them on a wild ride eventually ending with him dumping them into the water. Phouka was sometimes pictured as frightening creature with the head of an ass.
Puck was known as a shape shifter as well. He had many appearances. Sometimes he disguised himself as a horse, eagle, an ass, a rough, hairy creature and in one Irish story he was an old man.
To be mislead by a Puck was known as being 'puck-ledden.'