The iskoki (singular - iska) were a type of jinn found everywhere – in the skies, forests, hills, bodies of water and cities of men. Those whose names were known and who had a definite cult generally had a favorite kind of tree or some other specific locale where they liked to stay. In these places, sacrifices of sheep, goats or fowl were offered to them, each iskoki having its appropriate animal.
Sometimes the iskoki we re called y'an gabas (children of the east), or y'an jangare (children of Jangare). The latter referred to Jangare, a fabled city in the east that is invisible to men and which the iskoki are supposed to inhabit.
According to Greenberg, the iskoki that play such a central role in Maguzawa belief were generally held to be in finite in number, although some of them were known by name and had definite personalities and powers. It was around these named beings that the religious life of the Maguzawa revolved.
Sometimes the iskoki revealed themselves to worshipers through the medium of selected human beings. They were summoned by appropriate drum rhythms to possess the summoner, who wore a costume characteristic of the iskoki. The spectators then conversed directly with the iskoki, who spoke through the mouth of the one possessed.
Most of the time, however, the iskoki were said to live in their invisible city of Jangare. One of Greenberg’s guides placed Jangare in the vicinity of Argungu in western Hausa region, although it was also often identified with a town in the south of Kano province called Baw'da. Near the town gate of Baw'da was a famous baobab tree and a well, at the bottom of which the iskoki were said to dwell.
The iskoki were normally classified as white (good) and black (evil). For the most part, the black iskoki were regarded as kuffar and said to live in the countryside, while the white iskoki were thought of a s Muslim and said to live in towns and cities. Sometimes other criteria were used, such as when the massak'i (the weaver) was defined as a white spirit because he wove white cloth; or the Ba'awzini (the Touareg) was also called white because the Berber Touareg were light-skinned. The Maguzawa also said that the spirit might be white for a man who worshiped him, although he was black for everyone else. It was generally asserted that only black spirits caused illness and that white spirits were harmless, when in reality any spirit could be malevolent or good. In general, however, the most malignant diseases were said to be caused by black spirits.