Encountering the Massclaim Trap

Hidden roles are a common feature of social deduction games. Each player typically has a secret role assigned at the start of the game, with different roles having different powers or properties. Yet, if hidden roles are designed recklessly, they can completely break the game. This is the "massclaim trap".

The massclaim trap can be difficult to encounter because most published social deduction games have not fallen victim to it. By the time a board game reaches the shelves of a store, it has been playtested extensively, and any major flaws present in the initial design have almost certainly been corrected. Thus, to find examples of the massclaim trap, we can look to Mafia games, where custom setups are regularly played for the first time.

Mafia & an Introduction to Roles

As one of the oldest social deduction games, Mafia is highly popular in online forums, where users oftentimes create their own versions of the game rules, with no guarantee that the rules are balanced. Only the general structure of Mafia is retained: the game consists of a Town team and a Mafia team, where the Town team outnumbers the Mafia team approximately 4-to-1, but only the Mafia players know the roles of their teammates. Over the course of the game, the Town players attempt to determine which players belong to the Mafia team, while the Mafia players try to stay hidden.

In a custom setup of Mafia, the host adds their own combination of special roles to the game, in addition to Town and Mafia. Oftentimes, these special roles help balance the game by enabling players on the Town team to gain information about other players. For example, the Cop role plays for the Town team and may target one player per round in order to learn their role. As another example, the Doctor role also plays for the Town team and may target one player per round to protect them from elimination at the hands of the Mafia.

What is the Massclaim Trap?

Roles are initially secret, and a well-designed custom setup of Mafia will disincentivize players from outright revealing their own role at the start of the game. Yet, in some setups, players will determine that the best strategy is a massclaim, where every player reveals their role immediately. This is the massclaim trap, and it breaks the game. In a post on the MafiaScum forums, mith, an experienced Mafia player and forum administrator, calls out this exact issue. In a thread about common mistakes in setup design, he writes, “Another common one: Too many named roles. Often the strategy in such a game is an immediate massclaim, which forces Mafia in a bad spot - either the named roles are confirmed, or the Mafia must counterclaim and put themselves in a 50-50 situation.”

To elaborate, if a player reveals their role, the Mafia team has two counterplay options. Either they can do nothing to respond, or they can falsely claim the role themselves. In the former case, the Town will recognize that the original role claim is genuine, as no other players made an identical claim. This “confirms” the player’s role, meaning that the rest of the Town can fully trust this player. With all of the Town united behind one player, the job of finding the Mafia players becomes much easier. In the latter case, where one of the Mafia players falsely claims the role, the Mafia team is placed in an equally difficult position. With two players who have claimed the same role, the Town will recognize that one claim is true (the Town player), and one is false (the Mafia player). Thus, the probability of correctly identifying a player on the Mafia team skyrockets to 50-50. If this scenario is repeated multiple times through a massclaim, the balance of the game tilts overwhelmingly in favor of the Town team.

The Dark Reality of the Massclaim Trap

It would be an understatement to say that the massclaim trap only destroys the balance of a social deduction game. Rather, it destroys the game completely. The nature of social deduction games is that they involve hidden roles, and the core challenge of the game is to determine the roles of other players or prevent one's own role from being discovered. If every role becomes known through a massclaim, there is no challenge anymore. The enjoyment is hollowed out of the game, yet the game drags on until players formulaically follow the necessary steps to reach their win condition. Fortunately, it is possible to add hidden roles to a social deduction game while avoiding the massclaim trap, and different games have taken different approaches to this design challenge.

1. Fewer Special Roles

Most Mafia setups are not susceptible to the massclaim trap, in part because there are a limited number of special roles. In a 15-player game, there might be only 2–3 special roles on the Town team. The rest of the Town players are simply a regular Town member. Thus, most players on the Town team cannot truthfully claim a special role because they do not have one. Individual role claims are still possible, but the massclaim scenario is avoided, and the players on the Mafia team can continue to keep their role secret. Some social deduction games forgo special roles entirely, such that every player on the same team has the same role. This is the case in The Resistance, where every player is either a Resistance member or a Spy, and players gather information through missions.

2. Vulnerable Roles

The Resistance: Avalon expands on the original design of The Resistance by adding special roles, while ensuring that the game does not fall victim to the massclaim trap. This design is accomplished through the use of a “vulnerable” role (Merlin). In a typical setup, the Resistance team will include two special roles: Merlin and Percival, each of whom is granted unique information at the start of the game. In the final phase of the game, the Spy team can assassinate one player; if they choose Merlin, the Spy team wins the game. Thus, Merlin cannot role claim, because doing so would grant victory to the Spies. Moreover, Percival must think twice about claiming their role, because doing so would narrow down the list of potential Merlin players. As a result, the vulnerability of the Merlin role prevents a massclaim strategy from being effective.

3. Unused Roles

One Night Ultimate Werewolf embraces massclaims while ensuring that they do not break the game. The number of roles in the game will always equal the number of players in the game plus three, such that once each player is dealt a role card, three roles will go unused. In the event of a massclaim, a Werewolf can plausibly claim an unused role card without entering a 50-50 conflict with a Villager player. Thus, a role claim cannot fully be trusted, even in the absence of a counterclaim. A massclaim might be a good strategy for the Villager team, but it would hardly win the game outright. Furthermore, One Night Ultimate Werewolf includes role-swapping, which makes role claims unreliable even when they come from Villager players.

4. Free-for-All

In Coup, the concept of a massclaim is outright absurd due to the free-for-all nature of the game. There is no Town-equivalent team, or any team at all for that matter; the game is won or lost individually. Without teammates, there is rarely any strategic reason for players to willingly disclose information to other players. Rather, players keep their roles secret in order to deny information from their opponents. The free-for-all approach is also used in Love Letter, where massclaims are equally dubious.

How I Avoided the Massclaim Trap

The massclaim trap can be devastating, but a properly designed game should have no trouble avoiding it. In the design of Demon Summoner, I deliberately avoid adding special roles to the game precisely because of the massclaim trap. Aside from the one player with the Demon Summoner role, every player in the game has one of two roles: Righteous or Evil. Instead of using special roles, players gain information through observing the actions of other players (mainly, whether they capture or release demons). There are no special roles in the game because there is no need for them, and they would only risk that the game becomes broken by the massclaim trap.