Bear with me:

Every player plays as [i]another player[/i] playing [i]a character[/i] the player [i]they're playing as[/i] created. If enough of the community worked out which player was pretending to be which player, they'd be eliminated entirely, and whoever was playing as them (playing a character) would immediately skip to whoever [i]their[/i] 'character' was playing. Obviously, this would all have to be filtered through proxy accounts (ideally, other members of the site).

The actual plot/setting/general content of the game was irrelevant, because I'm an idiot that doesn't think about anything.
Nowadays, I try to go for more normal murder mysteries, except no. They're all fucking carnage.