Sartlar are the half-men that are used by the Masters everywhere throughout the Commonwealth as labour.

The largest proportion of the sartlar, by far, are those that are used to cultivate the vast agricultural spread of the Guarded Land. These are all identified by having had the 'Earth' glyph branded deep into their face. The diagrams show a sartlar marked in this way and also the iron with which the branding is done.