Two main magical traditions of Africa are separated by the Sahara Desert.
North And South of the Sahara Desert
The territory north of the Sahara is ruled by the Pharaoh dynasties characterized by ritualistic theocracy and strict customs, privileges and obligations.
From Sahara and to the south the magical traditions are much more scattered and diverse. The nomadic desert people, for example, have a much different view on the world of magic than the hunter-gatherer peoples form the tropic parts.
That is a group of magical traditions dominated by Shamanism and elemental magic (elements harnessed as a source of magical powers). They do not divide magic by its source or the toll it takes so the use of the black magic is pretty common. The "good" or "evil" of magic is judged only by its immediate effect so to them "black" and "evil" magic means something entirely different.
Constant Power Struggles
Because of the rich diversity of traditions Africa still doesn’t have a unified governing body for the world of magic. The Pharaohs are always trying to extend their rule far beyond its official boundaries while the other groups are either trying to join or resist them, depending on the current balance of power.
Under the pressure of the Pharaohs and relatively unrefined techniques of using magic, the southern neighbours of Egypt were forced to drain their sources of power quickly and intensely. With time it caused the expanse of the Sahara Desert.
The pyramids were then built as foci of power to prevent the desertification but not only did they not succeed, they accelerated the process. It turned out that the pyramids do not release any magical aura, but through the centuries they kept absorbing magical energy.
No one knows where all that energy goes, will the pyramids ever stop draining it and what will happen if they do. That is the reason there was never an attempt to stop their activity.
Famous Wizards Throughout History
Haile Selassie, Neferneferuaten Nefertiti