Hammer
From SA Mafia Wiki
The Hammer is the last vote needed to execute a player, usually joined with a :redhammer:. When the "hammer falls," typically the day is considered to have instantly ended - thus as per the standard mafia rules all posting should stop until the mod returns. If there is a Twilight phase, it usually occurs after the mod has posted the flip, but sometimes it means players can still post after the hammer. If there is a Governor role, between the hammer and the flip is when they need to decide whether to commute the execution. If the executed player is a Vengeful Townie, they also have this time to decide whom they would like to kill.
Scum often try to avoid being the hammer on a town execution, as whoever lays down the hammer tends to have their vote and reasoning scrutinized more than most other votes.
An Executioner can cause an execution to occur before hammer falls.