Mr. Bill's Adventureland
"A sinister, lurking presence in the dark places of the earth. Its favorite diet is either adventurers or enchanters, but its insatiable appetite is tempered by its horrible fear of light. No grues have ever been seen by the light of day, and only a few have been observed in their underground lairs. Of those who have seen grues, few ever survive their fearsome jaws to tell the tale. Grues have sharp claws and fangs, and an uncontrollable tendency to slaver and gurgle. They are certainly the most evil-tempered of all creatures... to say they are touchy is a dangerous understatement. 'Sour as a Grue' is a common expression, even among themselves."
So whatever you do... DON'T... and we mean NEVER... go underground without a lantern!