Nggwal is the supreme spirit of the Ilahita Arapesh men's cult, the tambaran to whom initiated males owe lifelong service and secrecy. Neither wholly ancestor nor wholly god, it is experienced as an unseen presence whose voice booms from within the towering korambo spirit house and whose favour secures the fertility of gardens, the increase of pigs and success in former warfare. Nggwal is fed with lavish feasts of pork and yams by the grade of men currently in its charge, and in return it underwrites their authority over women and the uninitiated, for whom the spirit is a genuine and fearful power. Tuzin records that the highest ritual of the cult is organised around Nggwal in two successive manifestations, the fierce Nggwal Bunafunei and the aged Nggwal Walipeine, through which senior men pass in the final phases of life. The fourth-grade cult of Nggwal was itself adopted from the Middle Sepik peoples and grafted onto the older indigenous tambaran of the Arapesh.