Across Arkham, strange doors to other worlds have been opening. They seem to be a living part of an ancient and arcane creature that has been reaching out, tempting the unwary with eldritch power. Now people are vanishing without a trace and it's up to a handful of bold investigators to confront the profane being who dwells just beyond these passages. But even working together, will they be able to destroy these unnatural and deadly gates without themselves striking a terrible bargain with the Lurker at the Threshold? This expansion for the Arkham Horror board game comes complete with one Herald Sheet, 18 new Gate markers, 110 new Ancient One cards, and 56 new Investigator cards, including new items, new spells, Relationship cards, and horrific Dark Pacts made with the powers from beyond.