 Many long dice provide further insurance against landing on end by giving the ends a rounded or peaked shape, rendering such an outcome physically impossible (at least on a flat solid surface).Design advantages of long dice include being relatively easy to create fair dice with an odd number of faces, and (for four-faced dice) being easier to roll than tetrahedral d4 dice (as found in many role-playing games).Both cubic dice and four-faced long dice are found as early as the mid third millennium BCE at Indus Valley Civilisation sites; these are marked variously with dot-and-ring figures, linear devices, and Indus Valley signs.