Infamous as a master of the dark arts and dirty dealing, few would associate John Constantine with Christmas, or any other holy day. Yet the Laughing Magician tapped the special magic born of the holiday season on two separate occasions to save the world and, albeit indirectly, Christmas itself.
The first incident occurred in Hellblazer #49, written by Garth Ennis with art by Steve Dillon. "Lord of the Dance" detailed how Constantine, desperately shopping at the last minute on Christmas Eve for a present for his new girlfriend, Kit, had an encounter with a ghostly figure in the form of a homeless man. Of course, such experiences are a frequent occurrence for John Constantine, but this one was unusual even by his standards. After Constantine confronted the man, he revealed himself as the Lord of the Dance; an ancient god of revelry, born of Yuletide, Saturnalia, and all the other mid-winter festivals pre-dating Christmas that were meant to celebrate life in defiance of death with feasting, drinking, mating, and (of course) dancing. Alas, such festivals were outlawed as Christianity took over England, leaving the Lord of the Dance in a bad state as more and more people forgot the reason for the season until the only people who noticed him were the psychically attuned like Constantine.
While John Constantine is usually the last to play at being a hero, even he could not ignore a god in need during the holidays. John invited the Lord of the Dance to join him at his favorite pub and treated him to a pint, asking him to stay and sit awhile with him and his friends. One pint quickly became several, as wild stories of parties long past were told and bawdy songs were sung, as the people who go to pubs on Christmas Eve having nowhere else to go began to join the growing celebration. It was not quite the revels of old, the Lord of the Dance admitted, but it was the exact same spirit that fueled him in ages past and a welcome reminder that there were still people who celebrate life in the middle of winter with a drink in hand and a song in their hearts. The grateful god would return the favor over a year later, organizing a last-minute party for John after he found himself all alone on his birthday.
Years later, John tapped the power of Christmas itself directly as part of a plan to save the world in Hellblazer #247, written by Andy Diggle with art by Leonardo Manco. Constantine had become the target of a blood mage called Mako because of a prophecy that claimed his downfall would come at the hands of the one called "the Laughing Magician." John was likewise warned that his death at Mako's hands would bring about the end of the world. Since Mako was an experienced soul-binder, who had already stolen the power and lives of many other magicians, John needed some kind of edge to even the odds.
Drawing inspiration from a book he'd stolen from the Vatican, Constantine found the edge he needed in the Basilica Di San Nicola; the final resting place of Bishop Agios Nickolaus, or, as he became known after his death, Saint Nicholas. One spot of graverobbing and several hours of intensive labor later, John had ground up Saint Nick's bones into a fine powder. Snorting the powder like cocaine, Constantine focused his will on a Coca Cola advertisement featuring Santa Claus and drew upon the belief of everyone who recognized Santa Claus as a figure of immense power. This gave Constantine the magic he needed to turn the tables on Mako and, as prophesized, trap Mako in a soul cage of his own design. An unorthodox plan, to be sure, but John Constantine technically did save Christmas and the world using magic borrowed from Santa Claus!