The disturbances in H.P. Lovecraft's New England don't stop at the Arkham city line. Nearby Dunwich is also being wracked by horrible events and otherworldly forces. Now, in addition to the threat of the ancient one awakening, the investigators will have to contend with the wrath of the Dunwich Horror... Dunwich Horror introduces several new game concepts to the Arkham Horror board game, including gate bursts, madness and injury cards, tasks and missions, and a new type of monster movement. Dunwich Horror also includes an expansion board featuring the village of Dunwich, 8 new investigators, 4 new ancient ones, over 20 new monster markers, dozens of new items and skills, and enough encounters to double the size of the location decks. All in all, the expansion adds over 300 new cards to the base game. Dunwich Horror requires a copy of Arkham Horrror to play.