- 1 x Active player marker
- 4 x Investigator 2 x Cultist
- 23 x Futile Investigation
- 1 x Cthulhu
- 6 x Elder Sign
- 16 x Insanity tokens
Object of the Game
Don't Mess with Cthulhu is a social deduction game with secret identities. Players are either Investigators trying to keep Cthulhu from waking and controlling the world, or Cultists that want to bring the world to a disturbing end.
The game takes place over four rounds. The Investigators must uncover all the Elder Signs to win; the Cultists win when Cthulhu is revealed or if the game ends before all the Elder Signs are discovered.
A fundamental rule of the game is that players may say anything that they want during the game (except to discuss the art on their Character token), regardless of the truth of their statements. Don't Mess with Cthulhu is a social game, pure logic is not enough to win.
Use the chart below to determine the number of Investigator and Cultist tokens to use in this game.
Shuffle the appropriate number of Character tokens, dealing one to each player face down. Each player secretly looks at the role assigned to them on the Character token. Place any unused Character tokens out of play without revealing them.
Randomly select a starting Active player, and give the Active Player marker to that player. Use the chart below to determine the number of Futile Investigation, Elder Sign and Cthulhu cards to use as the Investigation deck in this game. Place unused cards out of play.
Shuffle the appropriate number of Investigation cards, dealing five to each player face down. Beginning with the starting player, each player secretly looks at their Investigation cards and declares (truthfully or not) the number of Elder Sign and Cthulhu cards they were dealt.
Everyone shuffles their Investigation cards and places them in front of themselves.
Note: At the end of Set Up, each player will have five Investigation cards. They will know the number of Futile Investigation, Elder Sign and Cthulhu cards in front of them, but will not know which card is which.
As other players may have lied in their declaration, each player will only truly know what is in front of themselves.
Remember there is no need to tell the truth in this game, lying is allowed and encouraged. This is true for both the Investigators and Cultists - neither side should be entirely truthful.
There are many reasons why you will want to be careful about the information that you reveal or even lie so your identity is hidden.
Cultists will want to know where the Cthulhu is hidden as they can win by revealing a single card, so Investigators should be careful about revealing when they have Cthulhu.
Likewise, Cultists should be cautious about revealing too much information about where the Elder Signs lie.
As you play the game more, you'll discover a number of other reasons why telling the truth is not always advantageous to your team.
But, of course, sometimes being honest is the best strategy - knowing when to lie and when to be truthful is the key to a successful investigation.
The game consists of four rounds. Each round has a number of actions equal to the number of players in the game. For example, a game with five players would have five actions per round.
The Active player (the player with the Active Player marker) selects any Investigation card of any player other than themselves and places the Active Player marker on that card.
Everyone can, and should, provide their input, insight and devious deceptions to guide the decisions of the Active player, but in the end it is the Active player's decision.
The chosen card is revealed and placed in the center of the play area so that everyone can see. Check to see if the game ends (see below), then play proceeds with the player whose card was just revealed being given the Active Player marker and taking the next action.
Note: Once a card is revealed, it remains revealed and out of play for the remainder of the game.
Not every player will get to take an action each round, nor should you want everyone to have an equal number of actions. Investigators should be wary of letting Cultists take actions lest they reveal Cthulhu and end the game immediately.
The round ends after the number of actions taken in that round is equal to the number of players in the game.
Note: The number of revealed Investigation cards at the end of each round should be equal to the number of players multiplied by the round number.
For example, the second round of a five-player game is over when 10 Investigation cards have been revealed.
After completing the final action of each round, the remaining Investigation cards are shuffled together and dealt evenly between the players. The players secretly look at their Investigation cards, shuffle their cards and place them in front of themselves.
Players may declare (truthfully or not) what cards they have each round.
Note: At the beginning of each round, each player will have an equal number of Investigation cards - one less than they had the previous round.
They will know the number of Futile Investigation, Success and Fail cards in front of them, but will not know which card is which.
Play resumes in the next round with the Active player taking the first action. Rounds repeat until the game ends or four rounds have been completed.
End of the Game
The game ends immediately if the Cthulhu card is revealed, all Elder Sign cards are revealed or four rounds have been completed.
The Investigators win if all Elder Sign cards are revealed.
Note: The number of Elder Sign cards in play is always equal to the number of players.
The Cultists win if Cthulhu is revealed. The Cultists also win if the Investigators are unable to find all the Elder Signs in time (after four rounds).
Note: The game always ends before all the Investigation cards are revealed.
Example Round: The third round in a four-player game. Each player has three cards in front of themselves. The players have already revealed eight cards (3 Elder Signs, and 5 Futile Investigations).
Mary (Cultist) is the Active player and has the Cthulhu and two Futile Investigation cards face down in front of her (and doesn't know which card is which).
She says "I have the Elder Sign". Peyton (Investigator) actually has the Elder Sign and says, "Mary, you are clearly a Cultist as I really have the Elder Sign". Thomas (Investigator) seems to have been convinced that Mary is telling the truth.
Action 1 - Mary investigates one of Thomas' cards - flipping over a Futile Investigation. Thomas is now the Active player and will take the next action.
Action 2 - Thomas, convinced by Mary's claim to have the Elder Sign, chooses to investigate one of Mary's cards - flipping over a Futile Investigation (luckily for him and unluckily for her as she would have won if he had flipped over the Cthulhu card). Mary is now the Active player.
Action 3 - Mary wants Thomas to be the next to act, so she once again investigates him - flipping over another Futile Investigation. Thomas is now the Active player.
Action 4 - Thomas becomes suspicious of Mary's claims and decides to investigate Peyton - flipping over another Futile Investigation (which is unlucky for both Peyton and Thomas , if the fourth Elder Sign was flipped they would have won the game). Peyton is now the Active player.
Four actions have been completed (equal to the number of players), so the round is over. In total twelve cards have been revealed. Peyton takes the remaining face-down cards from each player, shuffles them and gives two cards to each player.
The players look at what cards they received, making any declarations that they want before shuffling their cards and placing them face-down in front of themselves so that they don't know which card is which.
The fourth and final round begins with Peyton taking the first action.
Optional Rules For Insanity Tokens
Don't Mess with Cthulhu is best played multiple times in a single sitting. After each game, give an Insanity token to all players on the losing team.
When any player has accumulated three Insanity tokens, the session is over and the player(s) with the lowest number of Insanity tokens wins.
Optional Rules For Three Players
It is possible to play with just three players. All the rules are the same, except in Set Up there are 3 Investigators and 2 Cultist tokens used and the Investigation deck is made of 11 Futile Investigation, 3 Elder Sign and 1 Cthulhu cards.
Note: It is entirely possible that all the players will be Investigators, in which case everyone loses if the Cultist win conditions are met.