First, anyone can have a bad night. Maybe that night was this guy's night. Talking to him is definitely the answer. Find out why he was doing it. Make a decision on whether you think he's really sorry or just sorry it blew up in his face.
I have a player who used to question a lot of my motivations and rules interpretations. He could get pretty passive-aggressive about it ("I'm not sure I can play in a campaign that works like that"). He's also my best friend and very much not like that outside of gaming. So, I used to bend a lot, just to keep things smooth. Sometimes, I wondered whose game it really was.
Finally, I got to the point where I was just ticked about it. He questioned the fairness of an encounter, the timing of it, and such things in an email to me. My response was to lay out the numbers for him, noting that this was the
last time I'd stand to justify things like that to him. I told him that he either trusted me as a DM or he didn't and if he trusted me, then he knew I was playing fair and not out to screw the characters or make things unfun for the players. I did
not chew his butt. I was very matter of fact about it.
Since that day, he's been pretty much exemplary in terms of abiding by my decisions, not questioning things, etc. Sure, he doesn't agree with every ruling I make, but he phrases things much more respectfully and cooperatively, now. I never need to worry about losing control of the game to him.
So, you never know. You may end up with an excellent player out of the deal.
gizmo33 said:
I have a rules-lawyer in my campaign right now. Rather than argue with him I treat him as just another rulebook. Rather than look things up in the book, I just ask him.
I'm not necessarily a rule-lawyer -- as in I don't try to find various loop-holes or that sort of thing. I have, however, played for over 20 years, almost exclusively as a DM. I suspect that I've consumed more pages of rules for 3.5 than anyone else in my group as for all the games they've played, combined. It's very, very hard for me to not spout off with an answer to any rules question. When I had the chance to play for a while, my DM used me in a similar way. Made things much easier for both of us.