In its simplest form, Mafia is played by two teams: the mafia and the innocents. Live games require a moderator who does not participate as a player, and identities are assigned by handing out cards. At the start of the game, every mafioso is given the identities of their teammates, whereas the innocents only receive the number of mafiosi in the game, and do not know which players are mafia and which are innocents.

There are two phases: night and day . At night, certain players secretly perform special actions; during day, players discuss and vote to "lynch", or eliminate, one player. These phases alternate with each other until all mafiosi have been eliminated or until the mafia outnumbers the innocents.