The act of driving a nail into a footprint is almost universally an act of maleficia, but not always. The details of what it does exactly vary somewhat by tradition but have been cited in folklore and folk spells as causing everything from lameness, to injury, to causing the footprinted individual to be completely unable to move until it is removed. It varies, honestly, and by quite a diverse margin, depending on the origin of the exact version of the myth and the ways in which the practice is recommended to be modified within the context of a specific version of the myth. Generally it’s a curse, though not in every single version. Again, there are variations.
