I'm getting off my ass and posting, since Taiga referred to me being quiet as "regular," and that I cannot have.
So, first off- Bergioyn specifically wanted 12 people for this game. That almost certainly means something beyond Vanilla Mafia is going on. You can do a simple "town vs. mafia" game with almost any number of players. Some thoughts:
-So it's possible we have an 8 vs. 4 game, with a doctor, a cop, probably at least one or two more roles (because we do love our roles, heh). Tracker or a watcher.
Scum would have a roleblocker at minimum, plus maybe Godfather and/or role cop (Can investigate people to see if they have a role).
-Since the emphasis is on 12, I feel like we probably DON'T have a serial killer. 8 town, 3 scum and a serial killer is pretty tough for the town.
We might have Town vs. Scum, with a cult...
-Or actually, You know what would be cool? MULTIPLE SERIAL KILLERS.
I'm thinking... 10 town, two serial killers? 9 town, three serial killers would be tough... Maybe 9 town, a vigilante, and two serial killers.
-A final possibility would be multiple, small groups- either 4 of 3 or 3 of 4 (Maybe 6 of 2?). This would be similar to the Wheel of Time game Isaac ran forever ago, where there were Aes Sedai, Black Ajah, Cairheinians, a couple Whitecloaks, and probably more that I'm forgetting.
In that case, I'm thinking something like 4 town, 4 team A, 4 team B.
tl;dr We're going to have multiple nightkills tonight, either from multiple groups or multiple serial killers, and at least a few of you probably want to kill me now for exposing you. So... remember me, doc, OK?
I feel like you're onto something about Berg wanting a strict game of 12. But I feel like we can make a bunch of guesses about the structure of the game and nothing will be solid until we see some deaths. I don't think it's too far a stretch to say we potentially have 3 groups but honestly, the number 12 could just mean he had roles perfectly balanced between 2 teams. I feel like it does say something but trying to guess what is like taking shots in the dark.
CS/CpE. Yay engineering!