Hercules is about to kill a three-headed giant, though the Wikipedia has: Geryon was often described as a monster with human faces. According to Hesiod Geryon had one body and three heads, whereas the tradition followed by Aeschylus gave him three bodies. A lost description by Stesichoros said that he has six hands and six feet and is winged; there are some mid-sixth-century Chalcidian vases portraying Geryon as winged. Some accounts state that he had six legs as well while others state that the three bodies were joined to one pair of legs. Apart from these bizarre features, his appearance was that of a warrior. He owned a two-headed hound named Orthrus, which was the brother of Cerberus, and a herd of magnificent red cattle that were guarded by Orthrus, and a herder Eurytion, son of Erytheia.

The cattle at least seems to be single-headed.