New Vegas. Not necessarily the focus, granted, but it's possible to complete relying mostly on persuasion. The main game anyway. Alpha Protocol also had some interesting (and reasonably important) persuasion mechanics, though the focus did remain on action/stealth.Nico III said:Probably wouldn't be much fun to play, but a silver-tongued deceiver would be interesting to experience - lie, mislead and bullshit your way to success! Persuasion mechanics have been in games before, but (as far as I know) never a character's primary means of operating.
There's also a choose-your-own-adventure type series on Choice of Games which is basically what you described, or at least it's possible to play as someone like that, but I guess you have to like the format.