Don in Mafia: what the role does
The don leads the three players against the town. From the second night the don checks one player a night, but learns something much narrower than the sheriff does: only whether that player is the sheriff.
What the don does at night
The don’s question is always the same one: is this the sheriff? Usually the answer is no. The don already knows the other two mafia from the start, so a check tells the don about one seat and nothing more. Beginners expect a third source of truth; there is none, and nobody at any point is handed a list.
How the don fits the team
The three against the town spend the first night learning who each other are and agreeing how they will choose a target. From the second night they choose one player to remove, and while they do, their leader hunts for the sheriff. The town wins only by voting out all three, so the don is one of the three votes it needs.
Free lesson: What each card can actually do
The seventh member of the town is the sheriff. From the second night, the sheriff checks one player and learns which side that player is on. And of the three against the town, one leads; that player is called the don. From the second night, the don checks one person to learn something much narrower — whether this is the sheriff. Usually the answer is no.
Free lesson: what each of the four cards can actually learn at night — and what nobody can.
The hand sign
The don’s sign is the thumb touching the ring finger, where a ring would sit. As with every role sign, it is a habit clubs share rather than something in the rulebook, and it can change from one room to the next.
Clubs share this sign as a habit; it is not in the rulebook, so ask your host which set your room uses.