The Hero of Crypt of the Sorcerer was a friend of Yaztromo who was staying in the Lion inn in Chalice when he or she heard the tale of a strange fissure near the Moonstone Hills. The hero rode to Yaztromo's Tower where the wizard related the story of Razaak and sent the hero on a mission to find Razaak's sword.
Upon returning with the sword and a companion, Symm, Yaztromo gave the hero a further task of acquiring a Gargantus horn before tackling Razaak in his lair. The hero succeeded with the aid of a Dwarf from Stonebridge called Borri, who had invented a hot-air balloon which the three allies used to increase their speed of travel.
It is possible for the hero to have taken part in other books, either before or afterwards. Since Borri invented the hot air balloon and in Shadowmaster their existence is reasonably well known, Crypt of the Sorcerer must have occurred first. When riding in Elumbar's hot-air balloon, Chadda Darkmane recalls travelling on the Galleykeep, but not in Borri's balloon, so it is unlikely that he is the hero.