At the centre of the festivities is Mann Manor, a macabre 'attack and defend' map that's festooned with exploding pumpkins and home to the Horseless Headless Horsemann. The spectre of Silas Mann, the Horsemann spawns seemingly at random on control points to chase after players with his bloody great chopper. If he's after you, you'll need to melee an enemy player to pass the curse on. Helping defeat the Horsemann, without dying, will earn you a pumpkin head hat, while whacking him in melee will get you Unusual Haunted Metal Scrap for crafting.
The haunted scrap can be used to craft four new Halloween hats--which can also be bought--as well as the Horseless Headless Horsemann's Headtaker axe. Even more hats come in the form of crude paper bags masks which spawn randomly in Mann Manor, and collecting all nine will net you a Saxton Hale mask.
You can also now buy Noise Makers, which play a variety of spooky Halloween noises, or Gift Wrap to give items that wouldn't usually be tradeable.
As well as Mann Manor, the update also adds the new map Mountain Lab. Both were based upon the same map from the TF2 Art Pass Contest.