I would LOVE to see this in games. It does happen as part of pre-scripted stories (you find you're working for the wrong side, or being played by one character against another).

While I could say a lot of positive things about this, I'd think it's more important to touch on some of the practical problems:

1) Audience: Would the audience be able to understand manipulative relationships that aren't a part of a fixed story (that explains who did what and why). You could do this in a very simple way, showing obvious gains and motives. An example would be someone telling you that there was an opportunity at a location, but when you arrive muggers are present.

2) Representation: How do you keep track of what's going on in a way that the player will understand from game to game session? What interface conveys emotion (that isn't astronomically expensive, btw) and motives?

3) Ruleset: What governs the success of a sneaky NPC while you're away? Do your friends and neighbors factor in in terms of thwarting or reporting him? To my mind, you can only make serious progress if you're willing to dive into this one, and it's a VERY difficult area because relationships have many variables and situational dependencies.

4) Sore Losers: I hate to say it, but I think we have little stomach for loss in games. So when this does happen, it can only be seen as a failure on the player's part. Normally, we've been conditioned that all failures should be immediately known and immediately correctable. So you're going to have to work hard to entice players to accept a loss they may find out about long after.

This would be a really great idea, so long as certain things are true. Namely, the player would need to be made aware before playing the game of the fact that NPCs might try to trick them. They're fair game after that, no pun intended. Still, there needs to be a way in most if not all of these duplicitous situations for the player character to be able to respond proactively to a given doublecross or attempted dupe. Otherwise, the player is going to feel like they're spending most of their time "putting out fires," so to speak. I know the world can be cutthroat, but please.

~Ranger Meldon~ M.M. .:

The player may accept loss if they see a chance for retribution. Though not instant retribution that would be rather pointless.

This could be a really cool system. I personally think though that you should expand this to encompass the idea that you can also manipulate the NPCs.

The one example that popped into my head was actually the TV series Andromeda. Basically the main character has to be wary of being manipulated by members of his crew etc, so he actually puts up measures of his own. So, in essence he knew he was being manipulated and was in turn able to manipulate the manipulators.

--Ter'Lenth

I've been playing with an idea along these lines. Put the player within a social/economic system where characters (player included) have levels of relations such as hate vs. love and fear. Characters themselves have personality traits that dictate how they react in different situations. To get ahead, the player has to use other characters and try not to get screwed over in the process.