by DoomTurtle
I've played 12 times, and the traitor has won 6 of those games (and I have yet to ever be the traitor). There are too many factors to determine who is going to win. Some haunts are easier with more heroes, some are easier with less heroes, usually because of the way some of them scale (or don't) based on number of players. Some of the haunts also depend on certain rooms or items, and if they are already out or easy to get to, then the heroes have an advantage from that. If the rooms/items aren't out yet, or the traitor blocks the path to a certain destination, then the traitor gets the advantage.Also, some haunts are heavy on certain skill checks, so the heroes chosen and their current stats also make the difference.
There's really no way to know what you are going to need before hte haunt begins, and by then its too late. You just have to go in to enjoy the experience, not to strategize a win.