GMing PVP

[CorralDust]

I'm running a play by post game on another site and that game is still in the very early stages. However, I've played with the other three players before and we have a good RP history. In the game, there is a small party of characters including mine and two of the other players.

The third player, accompanied by two NPCs under my control, is playing a law man and is after the bounty on one of the characters in the main group.

I've GMed single party RPs before, but usually they are cooperative affairs. Anyone GMed a scenario similar to this? How did it go? Any advice on how to keep things fun for everyone?

 

[CorralDust]

My plan, at least at the moment, is to try to give them a compelling enough reason to team up. Maybe a 'save the kid' kind of scenario. Which would shove it back into my GM comfort zone of running an adventure for a single party. But do you think that kind of set-up detracts from the fun of being a bounty hunter?