Vengeful Mafia

Vengeful is a 5-player Open Setup devised by Kelly Chen.

Roles

There are 2 mafia, one of whom is the "godfather." The other 3 players are townies.

Rules

The game uses standard mafia rules, with the following exceptions and details:

• The mafia can't kill at all. There is essentially no Night phase.
• If the godfather is lynched at any point, the town immediately wins. (This is the only special quality of the godfather.)
• If, on Day 1 only, one of the townies is lynched, this townie immediately gets to make a vigilante kill.
• The town does not automatically win by having the godfather killed in this way.
• Mafia wins when there are at least as many mafia as townies, and the town doesn't have a vengeance kill to use.

Odds

Assuming all lynch and vengeance decisions are made randomly, mafia will win 60% of games and town will win 40%.

The mafia's win odds are:

• 20% chance of godfather lynch D1 * 0% chance of mafia win in this case +
• 20% chance of second mafia lynch D1 * 75% chance to survive final four * 67% chance to survive final three +
• 60% chance of townie lynch D1 *
  • (50% chance of vig kill targeting a townie +
  • 50% chance of vig kill targeting mafia * 67% chance to survive final three)

Myths

1. Mafia should be able to win by quicklynching;

   However: Due to the lynched townie's vigilante kill, it's not likely that the mafia will be able to pull this off without losing a member. If it's obvious who the mafia are, one will be vigged, and the other lynched on Day 2.

1. Getting a vig kill D1 is almost as good as lynching scum on D1.

   However: If the town lynches one of the mafia D1, the town's odds of winning become 75%: 100% if the godfather is lynched, or 50% if the second mafia is lynched. On the other hand, when a townie is lynched D1, the town's odds drop to 16.7%: There is only a 50% chance that the town can even continue the game (by getting a mafia member vigged), and in this case there is only a 33% chance of going on to correctly lynch the remaining mafia in the final 3.

Seven-Player Variant

This version, for seven players, has nearly the same (perhaps exactly the same) 60%/40% win probabilities, according to a simulation. It has these differences:

• There are 3 mafia (one of whom is godfather) and 4 townies.
• It is still true that if the godfather is ever lynched (not vigged), the town automatically wins.
• A lynched townie gets to make a vig kill only when it is "Lynch or Lose" (i.e., if a vig kill were not made, mafia would immediately win) and there are at least four players for the townie to pick from.

History

The initial setup included 2 generic mafia and 3 townies. Anyone who died Day 1 was able to submit a nightkill, townie or scum, essentially keeping the town always at Lynch or Lose. The odds strongly favored mafia (76.7%), and skilled players could easily manipulate the town. This thinking led to Rosso Carne developing the so-called "Vengeful Gambit." Night 0, he told his scum partner to make small slips, and he would call out every single one of them continuously, and push extremely hard for his partner's lynch. After pushing the gambit, either Rosso was lynched, revealing scum, and half-confirming his partner, or his partner is lynched, making the town's trust of Rosso rise. Either way, the lynched mafia could make a nightkill, and with a town at LyLo day 2, scum would ride to an easy victory. In his next game, Rosso played smooth and actually made good arguments, and through reverse psychology, led to another scum win. The early games had no recorded town wins.

The early scum dominance (and indifference of scum to being lynched) led Kelly to add the rule saying a lynched mafioso would not get a nightkill. If town lynched good day 1, it would be 4v1 day 2. Still, this did not help town enough, as no town wins have been seen with this setup.

The next and current step in the evolution of this game is splitting the mafia into a GF and vanilla mafia. If the GF is ever lynched, the town wins. If the vanilla is lynched day 1, it goes to day 2. This greatly decreased the gambit play, as it was risky to obviously expose the mafia if one lynch could result in a loss.

One current trend is Mastermind of Sin's "pairing" system, wherein he makes pairs of the other 4 players, lynches one of a pair, and if that person is not scum, they vig the other person in the pair. The obvious problem is that if MoS is scum, he can manipulate the pairings to make conditions for a scum win easy. He's been lynched for making pairings 3 times thus far.

Update: Town has been winning a lot more often lately. It is much rarer to see townies ask to be lynched, or be obliged if they do. The town even manages to lynch the godfather D1, which formerly never happened. Players seem to be putting more time into creating and looking over voting patterns.