Basic Town Side Roles
Doctor - Protects one person a night. Is usually unable to protect from serial killers.
Cop - Investigates one person a night and learns their role. Sometimes referred to as 'Seer'.
Vigilante - Able to make one kill a night. Is usually unable to kill serial killers.
Basic Mafia Side Roles
Mob Boss - Responsible for sending in the vote for the Mafia side lynch. Replaced upon death. Some games go without and allow the mafia to come to a consensus.
Basic Sideless Roles
Serial Killer - Kills one person a night. Wins if everyone else dies. Usually immune to all kills beside lynch.
Extra Roles
These roles may or may not be in the game; it will usually be mentioned beforehand if they are.
These roles may or may not be in the game; it will usually be mentioned beforehand if they are.
Dancer - Stops one person daily from using their role. Sometimes referred to as 'role blocker'.
Psychic - Stops one person daily from voting. (Variation: changes their vote.) Sometimes referred to as 'vote blocker'.
Mad Scientist - Random effect (kill, investigate, protect, or roleblock) on target.
Spy - A Mafia member who, if investigated, turns up town. (Variation: Town member who turns up Mafia.)
Friends - Town members who start the game knowing each other's innocence. Usually 3 people. Sometimes referred to as 'masons'.
Siblings - A two-person variation on the Friends. They do not necessarily have to be on the same team, and they may even have an additional role, but if one dies, the other commits suicide the following night. Sometimes referred to as 'lovers'.
