From publisher blurb:
The dungeon and cavern dice are broken up into three sets of five dice each, with each set containing 30 different designs. See the links in the left sidebar's "DungeonMorph Dice" section for which set contains which designs. Each design on each die also contains a small letter denoting the die. ("P" for the Prison die, "B" for the Barracks die, etc.)
The cities, ruins and villages dice are also broken up into three sets: one of all city designs, one is just village designs and the third set is ruined versions of the city designs.