Me and another member of my group have agreed to swap GM duties every other campaign. So, for instance I'd run the Under the Black Sun adventure and then he would run the next one. With the Obligation system it shouldn't be too hard to make up a valid excuse for why these two characters disappear every once in a while, but I was just wondering if anyone else had tried a system like this and if there were any pitfalls we needed to watch out for. Thanks.

My suggestion is, "do it." As long as you keep your adventures episodic, there's no reason why swapping GMs isn't a good idea. You both get a chance to play characters, you both get practice as GMs, and it encourages the notion in players that, "hey, I could be a GM too!" I know that I want that from players in my gaming groups, so IMHO GM swapping is one of the best things you can do for yourself and for your gaming group.

Naw, dont sweat it - it's awesome! Me and a friend do this ALL the time (like years now) in our game without ill effect. Actually it's nice to change up the pitches every once in a while, since I tend to do big sweeping arcs with action and explosions and stuff and he's better at the more intimate stories, mind screws and character driven episodes. So we get a nice pacing and variety of stories in our mix (and hopefully if we can get a third player roped into GM duties, me and him might actually get to play at the same time! Shocking!)

As for having your character hanging around, treat them as you might a droid - they can come along, be occasionally useful when prompted by the characters, drop subtle (and non-subtle) hints if the plot needs a push in a certain direction - but otherwise, just leave them in the background and let the proper players have the spotlight.

Also, don't overlook the GMPC as a plot point. "You stay here and guard the ship while we go into town" - and the players aren't even out the hanger doors when the bounty hunter swoops in and kidnaps the GMPC. Boom! Instant motivation! Mind you, I don't tend to do that trope much anymore since it did get crazy overused for a while, but if I have the need, I wouldn't hesitate dusting it off again.

In regards to the experience points, don't worry about if you earned them or not - just keep parity with the rest of the group. That way you're not flopping around like a limp fish come 6 months down the line when you're playing.

Be sure not to GM when you're playing. There will be situations come up that just rub you the wrong way as a GM... bite your tongue and talk it out later. Play as a player (heck, even complain as a player) but don't knock each other's style - go with it. You'll get your turn again.

Oh and if he kills your character, don't take it out on his character when it's your turn.

Be sure not to GM when you're playing. There will be situations come up that just rub you the wrong way as a GM... bite your tongue and talk it out later. Play as a player (heck, even complain as a player) but don't knock each other's style - go with it. You'll get your turn again.

Oh and if he kills your character, don't take it out on his character when it's your turn.

I co-GMed a Dungeons and Dragons campaign like this for years. My only real advice is to be very clear with each other on what elements are in and out of bounds: on more than one occasion one of us would take another's NPC or plot thread and run with it a little, not realising we were inadvertently ruining plans the other had for that character or plot.

As with many things, it's going to depend on the group, the players, and the GMs' respective styles.

I played in a d20 Modern campaign that was based around G.I. Joe with two rotating GMs, and their styles of games couldn't have been more different. One ran his adventures as very serious and rather dark fare that you'd find in a Tom Clancy novel, while the other (who was more of a G.I. Joe fan to begin with) was a bit more light-hearted and included elements of silliness from both the cartoon and the comic books (such as the Dreadnoks subsisting entirely on chocolate doughnuts and grape soda, yet still having sparkly clean teeth). The campaign blew up when the two GMs simply couldn't agree on where to take the overall story arc.

I think the rotating GM idea works best of your campaign is more of an "adventure of the week" set-up without a major over-arching plot, much the way that many older TV shows (particularly those prior to Babylon 5 which proved that a series-long meta-arc could be done on television) where the group simply bounces from one adventure to the next, with no real common thread other than it's a similar group of characters each time.

It's probably best of the rotating GMs get together well ahead of time, and as windupmonkey said, lay out the boundaries as well as what the major campaign arc is going to be, as well as how to portray any recurring NPCs in the campaign. Few things can be as jarring to the players as the stern-but-fair base sergeant from the last couple sessions suddenly being portrayed as a smarmy backstabber the next session without any justification or explanation. Or that the Rebel Base they were assigned to suddenly changes from being located in a remote asteroid field on the outskirts of the system to now being on a moon orbiting the major population center of a different system simply because the GM for this session liked that idea better. And sadly, I've seen this happen, where one GM decides to change things "just because" without consideration for what the other GM(s) might think or have to say.

The other problem with a rotating GM set-up is that the players may find that they prefer the sessions run by a certain GM and come to dread the sessions run by one of the other GMs. I tried the co-GM thing with another guy to run a Deadlands: Hell on Earth campaign, and after a couple months, the players came to me and said they'd rather just have me as the sole GM for the campaign since I managed to strike that right balance of funny, creepy, and dangerous in the sessions I ran, where the other guy barely knew the rules and ran the game as though it were TOON or Paranoia.

I co-GMed a Dungeons and Dragons campaign like this for years. My only real advice is to be very clear with each other on what elements are in and out of bounds: on more than one occasion one of us would take another's NPC or plot thread and run with it a little, not realising we were inadvertently ruining plans the other had for that character or plot.

However, don't be afraid to talk to your co-GM. There's been many a time I've gone "Dude, I have the perfect idea for the bad guy your just created! Can I take it and run with it?" - and either get their blessing (and then it's game on) or they'll go "I had something in mind" and I'll back off. But communication can lead to some real nice chemistry between the two GM's.

Just ensure that if the players end up disliking one of the GMs, that issue is addressed before too long or your table may break up.

Just ensure that if the players end up disliking one of the GMs, that issue is addressed before too long or your table may break up.

Yeah, I like to leave some time after each game session to get some feedback from the players, and make changes if they found something particularly not-fun. This would be all the more important with multiple GMs, I feel.