The line to loot the Headless Horseman starts over here.
I'm not typically into the fluffy holiday events that game devs have become so keen to include. I don't have a burning desire to turn my mount into a reindeer, or get a snow globe for my house. What I do enjoy though is an occasional fat loot run with minimal time requirements. Hallow's End is just such an event in World of Warcraft. Starting right about the time I hit submit on this story, you should be able to head to the Scarlet Monestary and start thumping the headless one for a chance at some decent prizes. For the uninitiated, the Hallow's End event has many facets to the festival at all levels of the game, but the one everyone runs for is the Headless Horseman in the cemetery wing of the Scarlet Monastery.
The fight is fun, and he is no push over so you can't just auto attack and go grab an adult beverage. When he does drop like a sack of over-ripe pumpkins, he delivers some useful gear,3 riding brooms and the much coveted Sinister Squashling pet. So stop what you're doing and go try to get a squashling. I'll wait here.
For more information on the rest of the festival, stop by the official Hallow's End page.