From SA Mafia Wiki
Kingmaker is a Mafia game variant involving a variable amount of players, depending on the Moderator's preference. In the game, a team of Assassins attempt to take over a village, killing everyone save for themselves, while a King and his peasantry fights them back.
The game is very non-traditional, and has several rule changes. The biggest is that the town does not vote on their lynch choice. Instead, there is a player called the Kingmaker that chooses a player every Night to become King. During the following Day, the appointed King listens to the erst of the players in the thread and eventually decides who he will kill. The king's lynch choice ends the day. Nightkills are handled normally.
Any player, including the Assassins, can be King. The Kingmaker's goal is therefore to identify pro-town players and crown them King over the Assassins.
Kingmaker may contain power roles that are unique to its variant. The Hero is a pro-town role that, when targeted for a kill by the King, survives and kills the King instead. An outed Hero may not become King. Other power roles are the Knight, that protects a player from being nightkilled (similar to a Doctor, and the Anarchist, which can overthrow the King once per game to bring about democracy for one day.
Sample Role PMs Written by The Ninth Layer
VILLAGER: You are a loyal villager that is trying to help the kingdom rid themselves of Assassins! You have no real power right now, but you may try to influence the King to make sure he chooses Assassins to execute, and if the Kingmaker decides you're a good choice for King, you may end up executing some Assassins yourself! You win with the VILLAGE.
KINGMAKER: You are the newest member of a secret organization that looks out for the realm and makes sure that a good monarch, and not an Assassin, rules to land! While the last hundred years have been rough for your order (dodging the Kings' evil soldiers, that sort of thing), your order has finally found a new opportunity to bring light to the Kingdom again! Every night, you may send me two choices for King, one as your main choice and one as your backup in case the main choice dies. But be careful; some of your choices may end up being Assassins, and they're not going to be very helpful to your village's cause... So choose wisely! Also, since Assassins keep vigilant watch of the village to find the Kingmaker, you will be in mortal danger if you ever reveal or even hint at your role. You win with the VILLAGE!
HERO: You are the Hero of the village! After a long campaign of fighting dragons in distant lands and having sex with beautiful princesses after you rescue them from those dragons, you've returned to your hometown to retire. The town loves you and will fight fiercely to make sure you are not executed! In fact, if the King decides to kill you, the village will rise up in protest of the corrupt King and kill him instead! However, this ability isn't very useful if you're not executed, so you should probably stay quiet about what you can do. Also, Assassins will likely try and kill you above anyone else, so that's another good incentive to stay quiet. Once revealed as the Hero, you may not become King of the realm. You win with the VILLAGE!
ANARCHIST: You are an Anarchist! You are sick of evil tyrant kings that rule for themselves and realize that the best option for the town is to overthrow their King and embrace democracy! Once per game, at the beginning of a day, you may tell me (privately) that you'd like to start a revolution. The current King will be overthrown and people will vote to decide their lynch choice. After a lynch choice has been decided, the town will return to the old system of monarchy. Keep in mind that you should use your power to overthrow Kings you think are Assassins or otherwise harmful to the Village. Also, if you claim your role, you may not become King, so it is advisable that you stay in hiding. You win with the VILLAGE!
KNIGHT: You are a famed Knight! Hailing from a distant realm, you arrived in the Village to discover that Assassins were harming the Villagers! You nobly decided to stay and protect one Villager every night. When night begins, choose a player to watch over. If Assassins try to kill that player, they will see you standing guard and retreat cowardly back to their hideout! You may choose to protect yourself if you wish. However, you may not stand guard over the same person twice in a row. If you claim Knight, you will not become King, so it is advisable that you stay in hiding. You win with the VILLAGE!
ASSASSIN: You are a member of a band of Assassins that have secretly ruled the Kingdom for 100 years. You and your Assassin partner, OtherGuy, recently learned that a new Kingmaker has risen up among the townsfolk, and that he is appointing Kings in an attempt to rid your band from the Kingdom! The two of you must work together to defeat the Kingmaker's efforts before you are eliminated, and may plan together outside of this thread. Each night, the two of you may choose a target to kill. Also, there is a chance the Kingmaker may pick you or your brother as King, so try to look like a good little villager. You win with the ASSASSINS!