  Mafia (also called Werewolf) is a party game. The participants are divided
into two competing groups: citizens and a mafia. The objective is to eliminate
the opponent group. The game consists of two consecutive phases (day and night)
and a certain set of actions (e.g. lynching during day). The mafia members have
additional powers (knowing each other, killing during night) whereas the
citizens are more numerous.
  We propose a simple mathematical model of the game, which is essentially a
pure death process with discrete time. We find the closed-form solutions for
the mafia winning-chance, w(n,m), as well as for the evolution of the game.
Moreover, we investigate the discrete properties of results, as well as their
continuous-time approximations.
  It turns out that a relatively small number of the mafia members, i.e.
proportional to the square root of the total number of players, gives equal
winning-chance for both groups. Furthermore, the game strongly depends on the
parity of the total number of players.
