Kwazulu Monkeyman (UN-B-4005)
An example in recent history of one such calling was a particularly infamous invocation during a battle in the Anglo-African Zulu war of 1879.

Chief Tchala Namumba had been ordered by Zulu King Cetshwayo kaMpande to deal the British a bloody defeat at the forthcoming battle of Isandlwana. Overwhelmed by the superior technical forces of the British army, Chief Tchala turned to the magic that had been used in his family for generations to ensure a Zulu victory.

The cost of the 'Devil's Deal' was high - the sacrifice of his 3 wives and first born children - in return Namumba was to gain an ally of superhuman strength and ferocity that would lead him to certain victory.

The creature that the chieftain raised, a towering 9ft beast, was a fearful sight. And on January 22nd 1879 it led an army of brave Zulu warriors against the British encampment at Isandlwana, bringing about the slaughter of the infantry based there.