In some varieties of the 'fruit tree' wassail you are supposed to fire shotguns up through the branches of the trees to keep evil spirits away! I imagine that almost anyone or anything would be driven away by a bunch of cider-sodden loonies blasting off shotguns.
Victorian writers were fond of claiming that the name of my home town --- Walsall --- was originally 'Waes Heil' or 'Wassail'. It wasn't.
Anyway, a Merry Christmas and a Happy Wassail to you all, and since December 25th is my birthday, you can take the day off.