Co-GM/STing and GMless Games

Has anyone been/run games with multiple Storytellers/Game Masters? How did it go? What worked and what didn't? How did you split your responsibilities/work? Any advice or lifehacks you can share?

On a similar topic, what about GMless games? Do these lend themselves well to PbP? What was the experience like? Any suggestions on the systems or general advice?

We ran a Numenera game where we were going to round robin the GMing duties. We created a town, characters, a few rules about messing with the setting (don't blow up Our Town!) and then off we went. I think we got to the third GM before the game dwindled away.

The one thing to keep in mind is that with GM rights, you have access to all the hidden notes, so any secrets you want to keep from prior GMs you have to hide elsewhere.

For GMless games, which I've only done live so far and not PbP, they've been fun. Because I'm always the one bringing those to the table, I still play a teaching/moderating role, but at the end of the day a game with GM-less in mind works great. It's a lot of initial coaching/teaching, but eventually people stop looking to you for stuff since.

I'm very partial to Ben Robbin's Kingdom myself, though he's better known for the also GMless game Microscope.

Ironsworn is GMless/solo optional. I remember just "testing" solo play so I can learn the rules enough for group gaming. Next thing I knew it was three days later and I was still solo gaming. What an experience!

Co-GMing I've only done for West Marches, never at the table itself. What I think works best is just having a central log of stuff—hooks, new lore established, whatever. But that's bookkeeping and a lot of GM's aren't into that. I personally haven't lucked out at having good West Marches co-GMs.

I've done Co-DMing for a D&D game at a weekly online game (it's technically still ongoing tho we haven't met once for it in 2026, but it was going for ~6 months prior to that, and we're trying to kick it back up right now). It was a sequential DM situation, not concurrent, and it worked... ok... for that game and for our purposes.

There were 4 of us and all 4 were rotating through the DM role.

It wasn't what I would call a "serious" game, it was something me and a few buddies who all live in different states were doing basically just as an excuse to hang out each week.

I admittedly haven't seen much success in the past on similar collaborative ttrpgs projects (specifically, world building things). And a lot of STing and GMing is world building, so...

I have some degree of skepticism about the idea.

But I think pbp is a bit uniquely situated for something like this to be more successful.

For sequential GMing, it's a lot more obvious how the roles work out. When you're GM you're the GM for everything, just like normal and that's it. But for a concurrent GMing arrangement, it could get complicated. I don't think such a (concurrent) arrangement works at all for a "linear" campaign, frankly. I think you would have to do something more open world/sand box-y, to where the GMs can divide up "the world" and consistently portray the portion of it for which they're responsible. Whether that division is by geographic areas, or factions, or on an NPC-by-NPC basis all seem workable to me. Just depends on the nature of "the story".

For any game I think you don't want to spread the players out too much, even in pbp, because it just creates too much work for the GM(s), or for me at least - I don't want to have to be running essentially 5 different campaigns (writing 5 different GM-posts) when 5 players go 5 different directions.

And so, if the players are mostly "grouped up", of you divide the roles by region or faction, you could end up with large portions of time where... you're effectively solo-GMing. At which point what's the point of the Co-GM?

So I would personally envision it (without having any experience doing so) working best with GMs dividing it up by NPCs and maybe alternating "encounters" or scenes, where the Co-DMs can always step into an "unfilled" NPC role that emerges in the other GMs scene/encounter.

I dunno if that's "right", but that's how I'd see it working while being fun/engaging for both GMs.

Once upon a time, a GM quit a campaign I was very invested in, and I offered the crazy idea that me and another player instead become a 50/50 GM, with me handling heavy crunch and combats, and the other one handling everything else. And that gave the campaign another 1-2 sessions, and it was straining but seemed like it could work out, but then it gently crash-landed anyway due to stalling (not enough players for solid party dynamics, not enough momentum to keep the story from stalling).

I'm not opposed to trying again, but only for a campaign I'm sufficiently invested in, in the right way.

I tried this once here on this very site. For me, it was a learning experience.

On one hand, we were able to stretch a game out longer because I was willing to step in for another DM. The transition was fairly seamless, and they were reliable about answering questions regarding lore and whatnot as the campaign inched onward.

The problem side of it was that he had made arrangements with players to use books and rules during character creation that relied on resources I didn't have access to and, in one case, were contradictory to one another. Basically, the DM homebrewed a build for a player so that person could have the PC they wanted, but I didn't have a way to track it or access the supplements used.

I would definitely do it again. If for no other reason than I believe it's important for different people to take turns running games. However, I think an augmented session zero would be needed to sort out which books everyone has access to, to ensure this kind of thing doesn't happen again.

I did this twice. First one was a wash as a bunch of people went AWOL and the game died. The other one was a blast.

The failed game was GM-less and using Mythic GME to run the game. While I liked it in theory, in PbP it was agonizingly slow to reach any sort of consensus as to how things should progress. Not impossible, just very slow. I think that is why that game died. For something like that I definitely think it's better in person or via real time chat, just to keep the pace from dying.

The other one used rotating GMs and it worked really well. It was my first experience GMing something for some one else (I do a lot of solo-rp as well, so I had some experience running a game) an definitely something I would like to try again. Especially since I have been planning on running a game for ages now, but never really found the time and energy to set up an entire campaign.

So if there is any interest in setting up some sort of rotating GM game, I am very much interested.

I've had my fair share of cooperative storytelling games, and I have to admit, it's always been a blast. Everyone, even the DM, gets to have a taste of the unexpected.

I co-GMed West Marches games and they turned out pretty decent for what is was worth. It was fairly easy to prepare and rum those games, because it was a shared, persistent world, and the GMs could be players in other GMs runs, so you had a lot of basic material set up for you and only had to set up your little adventuring segment for whatever the players were going to do for the "session".

I also ran an unusual CoC campaign where I had a co-GM that was more like a player with extra privileges. They played a GMPC of my choosing and had some responsibilities with the players, abd made some rolls as well independent of me making rolls that had to do with the plot elements. That character would lead players on with hints and advice on how to run missions and provide some other tips, and occasionally provide direct support, while being an overall mysterious factor, while the characters went off and gathered information and did their missions and returned with more information to feed that character to mix up and parse and turn around give the players more clues and so on. It worked well enough with that co-GM, but the campaign was not the typical CoC campaign and so it sort of squealed to a halt under that weight, I think rather than the co-GmIng.

I was part of a game that actually had four co-GMs (of which I was one). We made up ground rules as part of session zero. Everyone used the same character generation rules, and everyone created a "stable" of three characters. We all agreed upon the character classes and races to be permitted (this was 2nd edition). When it was your turn to GM, you were allowed to use your own character as an NPC, but they only gained one-quarter experience for the session, and they were never given a choice of magic items they received (the items must be given to them by the other players). As a GM, you could award anything you wished to your players, but other GMs had the right to say that the character could not use specific items in their sessions.