|Born||In or around 181 AC, 182 AC or 183 AC|
|Book(s)||The Mystery Knight (appears)|
He had small, shrewd, close-set eyes with thin, arching eyebrows. He kept his black beard neat and had a receding hairline.
Uthor Underleaf was a professional tourney knight, who made his living off of wagering on jousts and the ransoms he gained for his wins. He preferred not to become a tourney champion, as he did not want to become famous, but was satisfied with the prizes granted to knight who came second. Ser Uthor would bribe the master of the games so that he would face the opponents he preferred -- big men, older champions past their prime, and "village heroes" -- where the odds would be appear to be against him.
When he defeated Duncan the Tall at the Whitewalls tourney, Uthor took Dunk's armor and horse as his win, and would have preferred to receive the ransom, but Dunk had no money to pay it. Uthor would not accept an IOU, but offered Dunk a place in his service, as a ringer -- someone who would appear to be a fearsome knight, who would get excellent odds when faced with Uthor at little tourneys across Westeros. Uthor thought that by the time news got around that Dunk was a hopeless jouster, they would have won enough money to buy a dragon's egg. Dunk refused the offer.
In his first joust, he unhorsed Ser Duncan the Tall in the first tilt. In his second joust he defeated Ser Addam Frey. After making Dunk his offer and divulging the story of Ser Glendon Flowers's knighthood and the fact that someone had bribed him to kill Duncan, Ser Uthor then defeated Ser Theomore Bulwer in five tilts. For his next tilt, he was to go against Ser Tommard Heddle, a match he had not been expecting. (Lord Gormon Peake had bribed the master of the games with a better offer than Uthor's, to make sure that Uthor would not face John the Fiddler or win the tourney.) However, the tourney was then interrupted by claims that a thief had stolen the grand prize of the tourney, Lord Butterwell's dragon egg.
Dunk: Ser Glendon has hero's blood.
Uthor: Oh, I do hope so. Hero's blood should be good for two to one. Whore's blood draws poorer odds.—-Duncan the Tall and Ser Uthor Underleaf 
The snail may leave a trail of slime behind him, but a little slime will do a man no harm... whilst if you dance with dragons, you must expect to burn.—- Ser Uthor Underleaf