A now obsolete luni-solar calendar used by the empire of Dor-en-Sann, dating from the traditional year of the founding of its capital city, Gaalkesh.

Its years were solar, but its months and weeks were determined by cycles of the two moons. In this respect it resembled the Hirerk Moonscale, though it was much less accurate, so that festival days were occasionally added by Imperial edict.

The calendar officially ended with the collapse of the empire, and the foundation of Orror from its ashes, around 1954 IC (3051 HM). In practice many parts of the old empire continued to use the calendar for nearly a century after, even in official documents and histories.