KrThonius was a black dragon living before and during the Age of Fire.
He was one of the three drakes in the Copper's training group during his time in the Drakwatch. He was athletic and strong, though not terribly smart. He left his first Drakwatch group when he was assigned to a sissa who patrolled the external rocky slopes covering the Lavadome in the Upper World.
He later replaced NeStirrath as the trainer of the Drakwatch.