As a small boy he had been a page to a wise scholar and magician who ruled much of Dawna. Treacherously, the boy murdered the magician, pushing him off the highest height of his castle. The boy used his former master's book of spells to turn himself into a giant. The spell, however, did not endow him with strength proportionate to his size; instead he remained as weak as the small boy he had been. Yet he managed to gain a reputation for fierceness through bluff and intimidation. His vivid red hair, and as he grew older his red beard, won him the title of the Red Rogue. (The Enchanted Island of Yew)
The giant amassed a following of thugs and criminals, and with them he was able to do some real evil. Most notably, he and his forces attacked the castle of Baron Merd of Heg; they defeated and killed the baron, destroyed his castle, dispersed his followers, and took Merd's daughter Sesely and her two attendants as prisoners.
When Prince Marvel and his friends eventually confronted the Red Rogue, the weak giant tried to use the old magician's craft to trick and defeat them. He captured all of Marvel's companions in a magic mirror; but Marvel's fairy nature safeguarded him from the spell. Marvel smashed one magic mirror, freeing the captives, and then caught the Red Rogue in another. With their leader gone, his men ran off, ending the threat they represented.
(A hundred years later, the magic mirror fell from its wall and shattered on the floor, and the Red Rogue was released. He discovered that the Island of Yew had turned civilized and respectable; his efforts to amass a band of followers and return to his days of power were completely ineffective. The giant was reduced to tending the garden of a local nobleman.)
Chris Dulabone employs the Red Rogue in his Do It for Oz.