Arkham Horror: The Card Game is a cooperative game for one to four players, with two core sets required for four players. Set in the world of H.P. Lovecraft's Cthulhu Mythos, players each take on the role of an investigator, each with their own unique set of skills and abilities represented by a deck of cards. The game is played through a series of adventures, or individual scenarios, that form a campaign. As players progress through the campaign and purchase new expansions, they have the opportunity to customize their investigator decks to fit their personal preferences and better prepare for challenges.

The Innsmouth Conspiracy is the sixth deluxe expansion for Arkham Horror: The Card Game and includes everything needed to begin a new campaign. The expansion includes two scenarios and five new investigators, as well as new cards to enhance and update various investigator decks. It also introduces new game mechanics such as Keys, Curse and Feast tokens, and Flood tokens. In order to fully complete the campaign story, players can also purchase the four scenario packs that complete the Innsmouth Conspiracy: In Too Deep, Devil Reef, Horror in High Gear, and A Light in the Fog. These scenario packs are not required to play The Innsmouth Conspiracy, but are necessary to fully experience the campaign story.

Please note that a copy of Arkham Horror: The Card Game is required to play The Innsmouth Conspiracy. The game is recommended for ages 14 and up and can take anywhere from 30 to 90 minutes to play, depending on the format.