This man communicates with the ancestors by making sacrifices with lambs, goats and chickens. When making sacrifices he uses sand, potions and writings.
If there is a disease or famine, he asks the ancestors to come help the people. He calls for the rain. When someone dies in the village in a bizarre ways, he is the one who investigates the death.
In most ethnic groups, there is an earth master. Everyone in the village respects this man and many are afraid. He's even well respected by the chief.