Four Winds;74348
The Mafia would be three people infected by the Thing looking to bump off the Townies and facilitate the Thing's escape from the frozen iceshelf.
Ooooh you know, prob a bit too much a radical change in the rules to be practical for now, and may not even work, but this made me think of an interesting variation for this...
If at the start of the game there was only one Mafia Thing, and they chose who they wanted to turn into The Thing. He is therefore the Godfather for the entire game. Instead of a Mafia hit, the mods would write a scene detailing a run in with the Thing with clues pointing at who the Thing/s are. No Mafia hits, just a subversive conversion. Perhaps the Things would not only nominate who to convert, but who to convert them. They'd make this call based on who already had suspicions towards them... to dilute the evidence, or to get use out of a condemned thing and avoid evidence pointing at others for as long as possible.
The townies, i.e. research staff, would need to kill off all the Things, their numbers dwindling and more of their allies becoming enemies as the game goes on. Plus they would probably get an idea if they'd lynched an innocent man if they didn't turn into some crazy beast when they try and kill them.
Instead of a doctor you'd probably have some kind of bodyguard. Where they choose who to protect on a particular night, and if that person gets attacked by the thing then the Thing would be beaten back, giving clues as to one or more of the thing's identity, or even (given the attacker is nominated) killing off the thing.
Issue with this is, of course, that for every lynching, a townie would be converted, probably making it impossible for the townies to win unless the conversions happened only every other day. I'm new to Mafia so there are likely 100s of other problems with this :D But something to think about for a future future future game, as i'm sure there'll be a way to make the numbers work and make it fun.