A mythical creature that may be confined to one area of Banffshire in Scotland, according to Walter Grigor in his ‘Notes on the folklore of NE Scotland’ published in 1881, the Yird Swine were a “dreaded ..animal” that lived in graveyards and burrowed through the earth feeding on the dead bodies.
They were described as a cross between a rabbit and a rat (which actually sounds like a stoat or ferret!) and hardly sounds particularly fearsome although I do not know of any other instances in Britain. Graveyards have always been the source of much folklore and there are many other creatures said to haunt them throughout Britain.
Lyndsay Mitchell in her book Hidden Scotland mentions that one place associated with the Yird Pig is the isolated Walla Kirkyard near the River Deveron in Banffshire. The churchyard may have had special significance in the past as there were reputedly two cloutie wells believed to cure eye infections.