A K'hartagh were Klingon 'holy men' that were located within nature preserves and other wilderness locations. These Klingons were charged with maintaining the peace between predator and prey as well as keeping the balance. They wore silvery purple and brown camoflaged ceremonial robes as well as a mask of wood with slit eyeshields that identify them in the wild.
The K'hartagh or K'hartaghan to maintain the balance are known to offer themselves as prey to the predators; giving their lives so this belief is continued. This essentially meant a trade of places. This is not done lightly for this only happens if there is a predator worthy of defeating them. (TOS novel: The Return)