We report highly ordered topographic patterns that form on the surface of diamond, span multiple length scales, and have a symmetry controlled by the precursor gas species used in electron-beam-induced etching (EBIE). The pattern formation dynamics reveals an etch rate anisotropy and an electron energy transfer pathway that is overlooked by existing EBIE models. We, therefore, modify established theory such that it explains our results and remains universally applicable to EBIE. The patterns can be exploited in controlled wetting, optical structuring, and other emerging applications that require nano- and microscale surface texturing of a wide band-gap material.