"If anyone at the kalends of January goes about as a stag or a bull; that is, making himself into a wild animal and dressing in the skin of a herd animal, and putting on the heads of beasts; those who in such wise transform themselves into the appearance of a wild animal, penance for three years because this is devilish.' (Margaret Murray, "The Witch-Cult in Western Europe)
Today is "Waldmännchentag" in some parts of Germany and Berchtoldstag in Switzerland - part of the "Rauhnächte" (the "Bleak Nights"), the continental variant of the Twelve Nights.
While English-speaking countries preserved the more gentle traditions like wassailing and pantomimes, Central European customs hint at things older and darker. The Rauhnächte are nights when the Wild Hunt is afoot, sometimes not led by Odin himself but the goddess Perchta. Especially on January 2nd, you should not do white laundry, lest the hunters come and steal it to make it your winding sheet over the year.
On Waldmännchentag all forest work is suspended or you'll meet a bugbear (the "Waldmännchen") in the woods, woken from his winter sleep and that's really bad cess.
The "Perchten", Perchta's entourage, walk the countryside during the "Rauhnächte" - watching if all the rules of good husbandry are observed, in the Alpine regions remembered by the "Perchtenlauf", with locals dressing up in spectacular demon costumes.
So, during the "Rauhnächte" and especially January 2nd, it's still the time to watch out without crying and pouting for not to anger the bugbears, Perchten or the Wild Hunt or what else that's out there during the Twelve Nights.
The wonderful Perchten masks pictured above are from an Austrian folklore society, the "Filzmooser Perchten" - there website is in German, but there are lots of fantastic photos from their "Perchtenlauf" to be found:
and more on: