Well, «Q» was a real challenge, hehe. In Dungeons & Dragons, particularly in the Forgotten Realms setting, a quaggoth is a bear-like inhabitant of the Underdark. As far as I can tell, there is no obvious mythoogical inspiration for this monster.
Quaggoths were humanoids with long, shaggy, white hair covering their entire bodies. They wore no clothing, with the leaders of packs being the exception.
Warlike and vicious, they roamed the Underdark looking for prey. Drow sometimes enslaved them as guards and spider handlers. Quaggoths spoke a halting form of Undercommon, and could grasp only simple concepts. More intelligent quaggoths could also speak a few words of the Duergar, Drow, or Common languages.
Quaggoths were nomadic hunters. They changed territories periodically. In each new territory, they claimed a central cave as a lair, leaving treasure with a few guards. The rest of the tribe hunted, returning periodically to rest and change guards. Quaggoths fear no creature. Though they were dangerous hunters, they were just as often prey for other predators of the Underdark. Quaggoths could be trained as servants and guards if captured young. Quaggoth tribes claimed a certain territory as theirs and patrolled it, hunting for food. Any animals or creatures (such as a party of adventurers) detected invited certain attack. Most tribes of quaggoths did not carry weapons, and attacked with their claws. The remainder of quaggoth tribes carried stone clubs or axes. Those quaggoths were or had been drow slaves carried superior weapons, such as steel battleaxes or two-handed swords.
In Forgotten Realms
Originally believed to have been bred by drow magicians as a slave race, the quaggoth escaped and filled their own niche in the Underdark. The origin of the quaggoths was unknown. Some sages claim that they were once a semi-civilized race that dominated much of the Underdark through conquest and ritual sacrifice, until the drow, duergar, and other races broke their power. Others speculated they had some sort of civilization on the surface and were driven underground; this theory was supported by the quaggoths’ hatred for surface-dwelling dwarves and elves. They did, however, have an underground kingdom called Ursadunthar, deep beneath the Spine of the World, until it fell to duergar from Gracklstugh in -1350 DR.