Nods.

As has oft been speculated, the image of Satan with horns and tail is thought to be an attempt by the early Christian missionaries to discredit the God/s of the polytheistic Nature-worshipers they were trying to convert.

One image of him is the personification of pure evil, the other evolved (in today's culture) in the personifican of pure generosity.

And one nickname for Satan is "Old Nick"...