Consequently, how many players do you need to play Mafia?
Realistically, the minimum number of players needed to play is seven (5 Innocents against 2 Mafia). The basic version described here requires a deck of cards and works best with between twelve and twenty-four players.
Then, what are the roles in Mafia game? The game has two alternating phases: first, a night role, during which those with night killing powers may covertly kill other players, and second, a day role, in which surviving players debate the identities of players and vote to eliminate a suspect.