Deepen your investigation with the best expansions for Arkham Horror 3rd Edition.
Arkham Horror 3rd Edition is already a rich cooperative experience, but its expansions are where the game truly stretches its wings. Each box adds new scenarios, investigators, and mechanics that evolve the base game rather than simply adding more of the same. This guide ranks them by overall quality, mechanical interest, and thematic payoff. All expansions are compatible with each other unless noted.
Expansion | 1-6 players
The most acclaimed expansion for Arkham Horror 3rd Edition. Dead of Night adds the Midnight Mask and Shattered Bonds scenarios, new investigators like Diana Stanley and Carolyn Fern, plus a haunting new set of mythos cards. It deepens the narrative and psychological horror of the base game without overwhelming new players.
Expansion | 1-6 players
A coastal campaign that sends investigators to Innsmouth and Kingsport. Under Dark Waves introduces two new scenarios with heavy maritime Lovecraftian dread, new Aquatic-trait monsters, and the Obsession mechanic that ties investigators' backstories to the mystery at hand. A standout for fans of the Innsmouth lore.
Expansion | 1-6 players
Secrets of the Order adds two new investigators and a cult-hunting scenario set in Arkham itself. The Silver Twilight Lodge mechanic lets investigators join or oppose the cult for strategic advantage at a narrative cost. Great for groups who want more decision-making tension built into the story.
Expansion | 1-6 players
Takes the investigation to South America with jungle exploration rules and a Serpent Cult to dismantle. Path of the Serpent features three linked scenarios, new Ancient One variants, and environmental hazard tokens that change how you move through the board. Best played after completing the base box.
Expansion | 1-6 players
Two new scenarios set aboard a train and ocean liner — moving environments that shift each round. Horrific Journeys is mechanically inventive with its transit board overlays and changing layouts mid-scenario. One of the most unique expansion experiences in the line.
Campaign Expansion | 1-6 players
A full campaign-style expansion with persistent consequences across five connected scenarios. The Innsmouth Conspiracy adds the returning Innsmouth Legacy track, where decisions carry forward between sessions. The closest Arkham Horror gets to a legacy-style campaign experience.
Start with Dead of Night — it's the most polished and universally loved. Innsmouth Conspiracy is essential if your group wants a campaign-style multi-session experience. Avoid buying all expansions at once; the base game alone takes 20+ plays to fully explore.
Arkham Horror 2nd Edition (2005) is the beloved classic cooperative Lovecraftian adventure. Its expansions are still widely played and collected. Here are the essential ones, ranked.
Large Box Expansion for 2nd Edition | 1-8 players
The best first expansion for Arkham Horror 2nd Edition. Dunwich Horror adds the town of Dunwich as a new board, a secondary monster threat that builds in the background, 8 new investigators, 4 new Ancient Ones, new items, and the herald and guardian mechanics that deepen every future game. Essential if you want more replayability without overwhelming complexity.
Large Box Expansion for 2nd Edition | 1-8 players
Innsmouth Horror adds the fishing town of Innsmouth as a new board and introduces Personal Stories — unique narrative objectives that give each investigator a personal arc beyond the main group goal. The deep one invasion mechanic adds a relentless parallel threat. Widely considered one of the best Arkham Horror expansions ever made for its thematic richness and mechanical depth.
Small Box Expansion for 2nd Edition | 1-8 players
The best small-box expansion for Arkham Horror 2nd Edition. The Black Goat of the Woods introduces Cult Membership — investigators can join dark cults for powerful benefits at the cost of growing corruption. The Corruption and Cult cards add a temptation layer that meaningfully changes how players approach every game. Excellent value for a small box with outsized impact.
Large Box Expansion for 2nd Edition | 1-8 players
Kingsport Horror adds the dreamlike coastal city of Kingsport as a new board, along with Epic Battle cards that change the final confrontation with the Ancient One. New Rifts mechanics open dimensional tears across the board, and Blessings and Curses add status effects to investigators. Best for experienced groups who want a more complex, multi-board campaign feel.
Large Box Expansion for 2nd Edition | 1-8 players
Miskatonic Horror is not a standalone expansion — it is a massive content patch for every other 2nd Edition expansion. It adds new cards, investigators, Ancient Ones, and errata fixes for every previous release. If you own two or more Arkham Horror 2E expansions, Miskatonic Horror makes them all better. Buy it last, after you have at least two other expansions.