Allow the host to check or uncheck the "First Attempt" option.
FIRST ATTEMPT:
Serial Killers comes up NS to the sheriff until they perform their first attempt at a kill. After that, sheriff detects.
Mass Murderers come up NS to the sheriff, and "has guns" (jail/vig/maf) to invest, until they perform their first spree. After that, sheriff detects, and invest sees the true vet/mm message.
Arsonists come up as NS to the sheriff, and "loner" to invest, if they have performed fewer than 3 dousings and have not burned anyone.
Once Arsonist performs their 3rd douse or 1st burn, sheriff detects and arson sees "has gas."
If the sheriff checks the NK on the same night that the NK performs their first kill attempt, first spree attempt, or 3rd dousing, then the sheriff DOES detect the NK, and invest sees the normal message.
Purpose of the Option:
1. To give the SK and MM a viable alternative strategy of hiding, and then waiting until later in the game before killing.
2. To give the ARS, the weakest of the NKs, a little extra advantage. Personally, I like to turn off sheriff being able to detect ARS in my saves. (But sheriff detecting SK and MM stays on, though my saves typically allow the MM to spree every night, even after a multi-kill)