The Emerald Knight — Diana Sheridan

Journeying to King Arthur's castle, wanting to be allowed to join the Round Table, Sir Randour meets Wynfarad, a young sorcerer. Attracted to each other, they soon join forces. Randour wishes to learn the identity of the father he never knew and also learn just what are the powers of the magic amulet embedded in his chest. Arthur, however, has a different challenge for the duo. To become one of Arthur's knights, Randour must first dispatch the monstrous fire-breathing beast Gwylldahr, which has been killing people, and setting houses and livestock afire. Yet so many before Randour have failed. When he and Wynfarad encounter the beast, and Gwylldahr turns on Wynfarad, Randour knows he must not fail if he wants to save his beloved's life. By the book's happy ending, Randour has learned the answers to his two questions, and the couple is looking forward to a happy future together in Camelot.