The Hallowed Fields is a zone made available through an online event around Halloween time. It can be entered from a portal on the world map once the player has collected 4 clues from Hallowed Ghosts as part of the Hunt for the legendary Plumpkin! quest. Note that the zone can only be entered once - the portal will remain on the map, but be inactive.
The Rod of Recall cannot be used to escape this zone.
The first floor of the zone is a Halloween themed forested area, populated by various skeletons and animated skulls and hands.
The second floor is a clearing in the forest, and the player will immediately encounter the Headless Horseman, a unique boss, after entering the level. There will also be many skeletal enemies nearby, as well as dreads. One should be prepared to fight these enemies immediately. Defeating the Headless Horseman will complete the Hunt for the legendary Plumpkin! quest, and grant the player the achievement Catch that Plumpkin!
After defeating the boss, there will be a large pumpkin in the center of the clearing. Walking over the pumpkin will allow the player to pickup the Plumpkin, which gives damage bonuses when carried in the inventory, and reveal the exit portal beneath it.