Among Ian Serraillier's other writings based on medieval sources are several verse narratives that relate the exploits of a famous central character. The Ivory Horn, an adaptation of the Old French epic The Song of Roland, depicts the heroic actions and death of Roland, the most preeminent of Charlemagne's knights. In The Challenge of the Green Knight (adapted from the Middle English romance Sir Gawain and the Green Knight), Serraillier retells one of the greatest adventures involving the figure of Sir Gawain, one of King Arthur's most valued knights. The adventures of the quasi-historical figure Robin Hood are treated in two of Serraillier's volumes, Robin in the Greenwood and Robin and His Merry Men. These volumes are based upon the ballads of Robin Hood that originated in early times.