The Mastermind 
Unseen Special
Can’t Touch This (Passive) - Immune to death at night, occupation and target changing. You will know if someone tries to occupy you or change your target.
Lurking Presence (Passive) - If you are killed within the first 3 nights your next in line will take your place as Mastermind, and you do not appear as Unseen to all investigations for those nights.
Dirty Work (Day) If there are no more Unseen members left, you can become The Assassin at the beginning of the night. - 1 use
Convert (Night) - Change target player into the Unseen version of their class. If you have failed to convert a target twice already and your next conversion would fail it will instead target a random convertible player. - Infinite uses, 1 night cooldown
Foresight (Night) - Determine a player’s converted class type, or if they cannot be converted. - 4 uses
Your objective is to defeat the Blue Dragon and any neutrals that seek to do you harm.
For newer players, the following addendum is made:
Always ask the hosts when in doubt. We don’t mind if we get 20 mechanical questions a day from you to ensure that you understand how the game works.
Read the original post carefully as many questions are already answered in there.
https://forum.imperium42.com/t/fol-class-cards-now-officially-official/1998 is where all the classcards are that are possible.
There are definite deviations from Throne of Lies the game, although many many similarities persist.
We have even completely new classes like Priest, Archer, Demon etc., so be sure to look at this link carefully. Small deviations for existing classes exist as well to provide a more forum balanced game.
An example is that a Knight can Cold Steel Night 1 already and a Physician’s Exhume only provides the faction of the dead person’s killer instead of the whole class.
The Cult functions very differently too and the following guide should provide some insight.
Cult points were added to allow for better fakeclaiming potential.
https://forum.imperium42.com/t/cult-points-how-do-they-work/62045
Feedback is also heavily reduced in comparison to Throne of Lies. For an feedback (exhaustive for at least the BD) guide follow:
https://forum.imperium42.com/t/forum-of-lies-hosting-feedback-guide/75082
Examples are that mainly investigative classes gain feedback. A butler occupying another player will not see if they are occupy immune or not. The player being occupied will not see that they are being occupied by anyone unless they are an investigative. Another example is that a Physician will not know whether their target was bleeding/poisoned and the target player will not know whether they are healed.
Trials also do not exist similar to Throne of Lies. That means when someone is “voted up”, they are immediately executed once majority is reached, so ensure that you stand behind your vote!
Forum players use a specific lingo and some common abbreviations can be found in the following link:
https://wiki.mafiascum.net/index.php?title=Commonly_Used_Abbreviations
Remember, when in doubt, ask the host: Frostwolf
