Leprechaun

In Irish mythology, a leprechaun (Irish: leipreachán) is a type of male fairy said to live in the island Ireland. They are a class of fairy folk" in Irish mythology and folklore, as with all fairies, with the Tuatha Dé Danann

What a Leprechaun typically looks like.

They usually form into the look of old men and who enjoy doing trouble. They are said to be very rich, having many treasure crocks buried during war-time. Legend says, if someone looks at one of them, the leprechaun cannot escape, but the moment the person looks away, he disappears.