Eldritch Horror: The Co-op Game, How It Plays and Its Expansions

What Eldritch Horror is

Eldritch Horror is a cooperative board game. Co-op means every player is on the same team, and you win or lose together against the game itself. Fantasy Flight's rulebook says it plainly on the first page of play: all players win or lose the game together.

Each player controls an investigator, a character with their own skills and starting gear. The team travels a world map, fights monsters, closes gates and works on Mysteries. Solve three of the Ancient One's Mysteries and you banish it. Run out of time and it wakes up.

The publisher's page describes it as based on the fiction of H.P. Lovecraft and inspired by the board game Arkham Horror. The character sheets are designed to look like worn passports, and the board is a yellowed world map. That's the mood. I'll leave the horror to the cards.

Here are the box facts for the base game, from the listing and Fantasy Flight:

• Players: 1 to 8
• Ages: 14+
• Play time: 120 to 240 minutes
• Co-op: yes
• Solo mode: yes, with optional one-player rules in the reference guide
• Contents (listing): 12 investigators, 300+ cards, 250 tokens
• Expansions: seven listed on Amazon US in our data, all needing this base game

The base box comes with two books: a rulebook to teach the game, and a reference guide for rules questions, exceptions and optional rules. The rulebook says on its first page that it skips many exceptions on purpose, so new players can learn the flow first. Two books for one game sounds like a lot until you see the card count.

How Eldritch Horror plays

The rules below are in my own words, from Fantasy Flight's Eldritch Horror rulebook. I've kept to the shape of a round. The card interactions are what the reference guide is for.

Before the first round

Pick an Ancient One. Its sheet sets the starting Doom and brings its own Mystery, Research and Special cards. The rulebook suggests Azathoth for a first game. Then build the Mythos deck by following the instructions at the bottom of the Ancient One's sheet. Then pick one player to hold the Lead Investigator token. Starting with that player and going clockwise, everyone chooses an investigator and puts the token on the board space shown on the back of their sheet.

The three phases of a round

Every round has three phases, always in this order.

1. Action Phase. Starting with the Lead Investigator and going around the table, each investigator takes up to two actions. Each action can be taken only once per round. In other words, no resting twice. I've tried to apply that rule to my lunch break. The actions are:

• Travel: move to an adjacent space, then spend train or ship tickets to go farther
• Rest: recover 1 health and 1 sanity, if no monster shares your space
• Trade: swap possessions with an investigator on your space
• Prepare for Travel: in a city, take a train or ship ticket, if a matching path connects
• Acquire Assets: in a city, roll an Influence test to gain cards from the reserve
• Component actions: actions printed on your cards or sheet

2. Encounter Phase. Starting with the Lead Investigator, each investigator resolves one encounter. If monsters share your space, you fight each of them, one at a time, in the order you choose. If not, you resolve a location encounter, or a token encounter like a clue or a gate on your space. Encounters are short story moments read off a card, with good or bad results. Fantasy Flight's page says a failed encounter can cost health or sanity, or hand you a Condition card such as an injury.

3. Mythos Phase. The Lead Investigator draws and resolves one Mythos card. Think of them as the game's own turn. They move Doom closer, open gates, spawn monsters and start Rumors that need dealing with. At the end of this phase, the Lead Investigator can hand the token to any player. Then a new round starts.

How you win

The team wins the moment it solves three of the Ancient One's Mysteries. Each Mystery card is a task, and the Ancient One's deck decides what kind. If the Ancient One wakes up before that, you also have to solve its Final Mystery to win.

How you lose

The rulebook lists the ways the board wins:

1. Doom reaches 0 and the Ancient One wakes up. The back of its sheet then says how you can still lose.
2. Every investigator has been eliminated.
3. You have to draw a Mythos card and the deck is empty.

That last one is my favorite rule in the box. The game can end because you ran out of calendar.

Teaching it to a new table

The Lead Investigator token is the closest thing this game has to a host. It decides who acts first in the Action and Encounter Phases, and it resolves the Mythos card. The rulebook lets the holder pass it to anyone at the end of each round. For a first game, my advice is to hand it to whoever read the rulebook, and keep it there for a round or two while everyone else learns the rhythm.

Then read the Mythos card out loud every round. It's where the threats come from, and a table that hears it together plans together. That's the whole point of a co-op game.

Making it easier or harder

Fantasy Flight's page says the Mythos cards come in three difficulty levels, and you can pull out the easier or the harder ones when you build the deck. The reference guide has the optional rules for that, and for scoring a game at the end. For a first game, the rulebook's Azathoth suggestion is the place to start.

Dana's ruling: anything with a 240 on the side of the box starts on a day she isn't working a night shift, so somebody at the table is awake enough to call it.

Eldritch Horror on Amazon US right now

Our data for this page lists 8 Eldritch Horror listings on Amazon US as of October 2026: the base game and seven expansions, all under the Asmodee brand on the listing. The table above shows what each states. Every one of them lists 1 to 8 players, ages 14+ and 120 to 240 minutes, so the table won't help you choose. What's inside will.

Eldritch Horror (the base game)

The listing says 1 to 8 players, 14+, 120 to 240 minutes, solo mode, and names 12 investigators, 300+ cards and 250 tokens. It's the only listing on this page that isn't an expansion. Start here, whatever else you buy.

The expansions, from Fantasy Flight's rulebooks

Every expansion listing in our data is marked as an expansion. Three of them, Strange Remnants, Signs of Carcosa and The Dreamlands, also name "Eldritch Horror" as the base game required. Here's what each adds, from the rules Fantasy Flight publishes for it:

• Forsaken Lore: mostly cards. Its component list starts with a new Ancient One sheet and 148 encounter cards, plus new Mystery, Mythos, Asset, Condition and Spell cards and a few Monster tokens.
• Mountains of Madness: an expedition to Antarctica on a new side board, with new investigators, Ancient Ones and Monsters, plus Unique Assets, the Focus action and Task Assets.
• Strange Remnants: a new Ancient One, investigators and Monsters, with Prelude cards that change setup, Adventures, Mystic Ruins encounters, the Focus action and Unique Assets.
• Under the Pyramids: an expedition beneath the pyramids of Giza on a new side board, with new investigators, Ancient Ones and Monsters, Unique Assets and Impairment tokens.
• Signs of Carcosa: 4 investigators and a new Ancient One, with Unique Assets and Impairment tokens.
• The Dreamlands: two new Ancient Ones, new investigators and Monsters, with Prelude cards, Unique Assets and Focus tokens.
• Cities in Ruin: 4 investigators and a new Ancient One, with Disasters, Devastation encounters and Unique Assets.

Marisol looked at a base game plus seven expansions and asked where the storage plan was. "Eight boxes is a survey with more appendices than map," she said. She has a point, and a shelf she'd like back.

Get the most from the base box first

There's a lot in the base box already. Four Ancient Ones, twelve investigators and three hundred-some cards is plenty of variety for a group that plays a few times a year. The expansions add investigators, Ancient Ones and new rules on top, and three of them add whole side boards. Each new mechanic, like Focus or Impairment or Disasters, is one more thing to teach before the first Mythos card comes out.

So the base game is the first purchase for everyone. After that, the expansions split two ways. Forsaken Lore, Signs of Carcosa and Cities in Ruin come as smaller sets of cards and tokens. Mountains of Madness and Under the Pyramids each bring a new side board. If your table space is already tight, that's the line to look at.

Who should skip Eldritch Horror

Skip it if your group wants to compete. Everyone wins or loses together, and a player who likes beating the person across the table will be bored or bossy.

Skip it if your game nights run under two hours. Every listing says 120 to 240 minutes, and that's before setup. A table that wants three games in an evening wants different games.

Skip it for younger players if you go by the box. All eight listings say 14+, with no exceptions in the expansions.

And skip it if losing to the board ruins your night. Cooperative games can and do beat the whole table, and this one has three separate ways to do it.

If you like Eldritch Horror, look at these

Pages chosen by what they share with Eldritch Horror: a cooperative game, a long evening, a bigger table.

• Pandemic: another pick for a table that likes to plan together
• Spirit Island: strategy for a group that likes a long evening
• Gloomhaven: another game for a group that plays together often
• Betrayal at House on the Hill: another game built for a bigger table
• Strategy board games: the wider shelf of long, planning-heavy games

Read the rulebook first, keep the reference guide close, and start with Azathoth.