A game that uses a "hidden roles" mechanic requires you to hide your goals and abilities from the rest of your friends. Different from strategy games, which benefit from some secret-keeping and have a plethora of interlocking ways to win, hidden role games focus on the secret-keeping aspect as a primary mechanic and amplify this by having a few opposing teams and clear and simple goals. Most themes involve a small, evil group or singular antagonist trying to deceive their way to victory by blending into a larger, less-informed group. This mechanic not only makes for a great stand-alone game but pairs well with most other co-operative mechanics as a secondary device.
Hidden role games succeed at creating tense, often paranoid, game sessions by pitting you against the powers of persuasion, deduction, and deception of your opponents, rather than their experience or knowledge of the game rules. The interest comes from not knowing who is on your side and who is your enemy. To this end, most purely hidden role games are very open and conversational. They refrain from using strict structures like turn-order or currency to create both the moment where two friends are staring at each other, trying to decide if they can trust someone they've known since pre-school and the moment when all is revealed and you can admire each others' intelligence. Most cultures consider the ability to prank or otherwise deceive someone as a sign of intelligence and wit. Hidden role games are a fantastic way to test your mettle as a liar and detective.
One of the oldest and longest-standing hidden role games is Mafia, the definitive classic of the genre. Created by Dmitry Davydov in 1987, Mafia is a role-playing game where a small, evil group of murderous gangsters are making a run for power in a small town. The goal of the mafia is to seize a majority of the larger, less-informed population by any means necessary, killing in the night and turning the citizens against each other during the day. Meanwhile, the uninformed majority are trying to root them out and save their town. You might recognize this game as Werewolf, which is nearly the same game, re-themed in 1997 by one Andrew Plotkin.
Mafia is a classic for many reasons. The goals are simple and clear. All you need is a regular deck of playing cards to assign the secret roles. With no formal mechanics, it allows for open conversation and direct accusation and defense. It's a brilliant game and many people's first taste of a pure hidden role game. It contains many of the most common sub-mechanics of hidden roles and also represents almost everything that is good and bad about them.
Let's dive in.
The Night Phase
When you have two secret teams, you often need a way to know who's who. In Mafia, most of the players are civilians and don't know anything about the other players. However, the Mafia need to know who each other are and need to work together to take over the town. The Night Phase allows this to happen. During a Night Phase, all players close their eyes, giving the smaller group a chance to open their eyes and acknowledge each other. This knowledge gives them a balancing advantage against their much larger opponents. A single game of Mafia has many Night Phases as part of its game cycle.
The Night Phase is a simple and effective tool with few drawbacks. The dependency on silence leaves an opening for a game-spoiling laugh or whisper, so Night Phases usually involve a form of distraction: feet-stomping, hand-clapping, and the like. They also require some guidance, which can be remedied by the use of a recording or by employing:
A Moderator, our second sub-mechanic
The Moderator or Narrator is a staple of pure hidden role games. This omniscient player sees over the game to make sure everything is going smoothly. They play to serve the game by facilitating Night Phases, informing of deaths in the night, handing down the will of the people, etc. Good Moderators can help build on the atmosphere of paranoia with how they portray information. Did "the Werewolves kill Jeff, I'm sorry" or did "the town gather at dawn, still shaken from yesterday's trial, to find poor Jeff in the square, claw marks down his back, still clutching the bottle he was enjoying that very night".
Some players enjoy the experience of being the Narrator to the story, almost a light dungeon master to the story of this town, directing the tone of the game. Some groups have a hard time choosing a Moderator, seeing it as a person who doesn't get to play the game. They are required to know everything so they miss out on the mystery that everyone else gets to enjoy. To this end, many uses of the hidden role mechanic get around this by only having one traitor or by using a recording to navigate any Night Phases.
The final sub-mechanic common in hidden-role games player elimination. Mafia has two: a player falling victim to the mafia during every night phase and one player voted out via a majority during the day.
Elimination is actually one of the largest weaknesses of Mafia and Werewolf. The first night and first day of Mafia see the elimination of players before a real basis of suspicion. It's arbitrary at best and often punishes veteran players. Eliminated players are simply out of the game. They cannot reveal their true identity, they immediately learn all the roles at the next Night Phase, and cannot interact with the other players. Unfortunately, elimination is essential to the theme and stakes of Mafia. If you cannot convince the citizens of the town that you're innocent, you cannot play anymore. Meanwhile, the mafiosi are more than happy to eliminate you: it is crucial to their goal.
Another major drawback of the hidden-role mechanic is the necessity for what I'm going to refer to as pot-stirring. Anything that sows well-founded suspicion is stirring the pot and contributes to the overall mechanic. Mafia doesn't have any mechanics that stir the pot. The Detective can reveal themselves and the information that they have, but this is often a death sentence and requires the Detective to survive multiple rounds to gain enough information and credibility.
I've seen many a game slip by as the mafia sit quietly during the day. The only strategy is to blend in and saying nothing is a frustratingly effective strategy that shrugs off most suspicion. Games with large groups can actually pass without any genuine reason to accuse anyone. It's tragic to behold.
Lucky for us, the hidden-role game is very popular. Mafia was certainly my introduction to games outside of the family block and are wildly influential on my collection and my designs. Likewise, there tons of games that feature the hidden-role mechanic and they provide many good solutions to these issues.
Democracy and Mental Elimination
Many modern hidden-role games have done away with player elimination. This requires adding a mechanic to track victory progress but the trade-off is worth it. Having all players involved throughout the whole game requires players to mentally eliminate other players and gives ruled-out players a chance to regain trust.
A popular replacement for elimination is the use of a democracy mechanic. Hidden-role games that employ democracy involve selecting and voting on a trusted sub-group that then has the power to progress the game for one of the two teams. Dystopian classic The Resistance does this masterfully by having all the players craft a team of soldiers to carry out a mission against the corrupt government. A single spy on this team can cause the mission to fail, which is important when both teams win by having three missions to go their way. The politically-themed success Secret Hitler improves on this by forbidding previously elected members from being in the next government, forcing you to work with people you don't necessarily trust.
The Democracy mechanic also sets itself apart by being an amazing pot-stirrer. If a mission goes wrong, you clear set of suspects. Better yet, you need every trustworthy person to succeed, providing a sound reason to give suspicious players a second chance.
Special Roles and Powers
While the basic version of Mafia is a great game, the most popular version included two special roles: a Doctor and a Detective. These two characters are part of the larger population trying to root out the mafia. However, they have abilities that allow them to assist in the search. The Detective gets a chance each Night Phase to wake up and ask the Moderator if a certain person is in the Mafia or not. The Doctor wakes up each night and can save the target of the mafia if they choose correctly.
Despite normally needing a Moderator, special roles and powers are an extremely positive addition to the hidden role mechanic. The powers are balanced by having a target painted on your back and rules forbidding the revealing of your identity card allows anyone to claim to be any special role, truthfully or not. They also add variety to the play that makes games interesting for veteran players and larger groups.
They also give the deceiving party more strategies of engagement besides looking as innocent as possible. For example, adding a Scapegoat to Werewolf (who claims sole victory if they are voted out during the day) gives the wolves the option to look more suspicious without outing themselves, encouraging bolder actions and pot-stirring.
Unfortunately, many special roles exacerbate a minor problem with the hidden role mechanic: high minimum number of players. The need for a smaller team against a larger group mathematically requires 5 players or more, which is the participant range of the most popular hidden-role games. Most mainstream games play much better with 7 players or more. Secret Hitler actually switches to a more compelling set of rules, when you have more than 6 players, that adds intrigue missing if you play with 5 or 6 players. Games can get around this by only having one traitor or by creating a more poker-esque experience with more deduction than deception, like with the amazing Love Letter.
Games that can support fewer players capitalize on a positive side-effect of hidden-role games that helps with pot-stirring: the natural rolling over of suspicion from game to game. The first game of Mafia at a party usually pales in comparison to the following games as the mistrust and alliances of the previous game affect the initial web of trust. Micro-narratives of betrayal and redemption stir the pot nicely, making games with shorter playtime easier to enjoy.
Hidden-role games are a fascinating staple of tabletop and role-playing games. Their simplicity and portability make them an easy choice in many casual environments. Few can resist the chance to test their wits against their friends and slip into a world where knowing if your best friend is lying can spell the difference between world peace and world domination.
There's a reason hidden-role games saturate my collection. They can take a brilliant, conflict-free co-operative game like Mysterium and turn it into the tense who-done-it mystery found in Deception. Given the choice, you can usually find me turning my back on those beautiful haunted halls in favor of the gritty neon of Hong Kong.
Why don't you come? You trust me, don't you?
From least to most intense.
Love Letter is a masterpiece of balance. With only 13 cards, this incredible microgame is a great introduction to deduction games that everyone should own.
Mafia / Werewolf
Many write-ups of these folk games exist but Mathew Sisson sets himself apart by providing a very clear set of rules on how to play, along with a gorgeous deck if you want to upgrade from a standard deck of cards: https://www.playwerewolf.co/rules/.
For the record, in Mafia you start with a third of the players being mafiosa and Werewolf always starts with 2 werewolves. Other than that, they are the same game. The Werewolf theme makes for better narration and is an easier-to-digest killer-by-night, normal-by-day concept, so I prefer that theme regardless of ratio.
Deception: Murder in Hong Kong
A great asymmetrical murder mystery where one secret player has committed the crime and one player knows all but can only give clues. Plus: who doesn't want a game that can seat 4-12 players?
The Resistance / Secret Hitler
These games exemplify the best of the genre. Sessions of these games can make lasting stories because they enable borderline traumatic betrayals. You also have a choice with The Resistance between the simplicity of the original and the "sequel" with many special roles: The Resistance Avalon, a better game critically and among veteran players.