In an economy of hoe-cultivation on rocky hillsides, rain is the decisive good, and the rites surrounding it are the most elaborate in Nuba religion. The rain is treated as a power that can be angered, coaxed, and controlled: its failure spells famine, and blame falls on both offended spirits and the human specialist charged with securing it. Among the Nyimang and comparable communities that specialist is a hereditary rain-chief who guards sacred rain-stones and other medicines and performs the seasonal rites at fixed places. Whether the rain is an independent numen or merely the working of the distant sky god is not consistently resolved in the sources; in practice it is addressed as a power in its own right, and its mastery is also claimed by the possessed diviner.