This variety of Mermen is very rowdy, and has the ability to cause storms at sea. They can be found in the North Atlantic from Scotland to New York, though they are most commonly encountered in the waters around the Outer Hebrides and the Minch. The Blue Men live in underwater caves. Though difficult, it is possible to get by them by distracting them with riddles and rhymes. They may be the decendents of Moors who were enslaved by Norsemen going Viking and subsequently abandoned in the Minch during the 9th century.
They differ from ordinary mermen in appearance in that they are totally blue and have grey beards.
They are also called Na Fir Ghorma.