How the Wonk GMs: Session Prep

Welcome back to How the Wonk GMs! Last time we had a bit of an introduction, framing the GMing experience by talking about campaigns and how one sets up for a campaign. Today, the discussion will be more specific, talking about how one gets ready to run a session. Later, I’m going to go into what I actually do in the GM’s chair, and what running a session looks like.

The one comment I got on the last post in this series was that it was vague, and I concede that. Here’s the thing, though: After you frame up what kind of campaign you want to run, what conceits and systems would be fun for you, you want to keep it vague. An RPG campaign is not a novel, and when you’re setting everything up prior to play you want to leave as many doors open as possible. It is now, when you’re looking to set up an actual session that your players are going to show up to, that you can start closing the doors and settling on what you actually want the game to look like.

I call this session prep, but in the real world with schedule breakdowns, cliffhangers, and everything taking just a bit longer than you’d expect, this might be more of an ‘adventure prep’ given that some of these ‘sessions’ will last two or three. For the most part, then, we’re going to be talking in units of plot rather than units of time. For each of these units of plot, you’re going to be figuring out a problem statement, a problem space, and then a problem resolution. When you’re prepping, though, you start with the problem resolution from last time, use that to write your new problem statement, and then use the new problem statement and your existing prep to define a problem space.

Problem Resolution

Session prep always begins by asking yourself ‘what happened last time?’ The characters accomplished something, failed to accomplish something, helped someone, pissed someone off, or any combination of these things as well as others. In continuing on from this point, you need to decide if there is more to happen in this conflict, and how soon that ‘more’ is going to occur. One general guideline here is that the earlier you are in your campaign, the more likely your answer is yes. In the first third or so of your campaign, every resolved problem statement should fractalize into two or three more. In the middle area, you either need mostly throughlines or a combination of some reedy, tough fractal problems with ones that the PCs actually solve and put to bed. In the back third of the campaign, the problems should mostly either tie off or fall into your intended climax.

Part of problem resolution is checking in on your dramatis personae, all the people and organizations that are important in your campaign, and seeing what they’re doing. If they’re directly affected by the actions of the last session that should be relatively clear, while if they weren’t really involved you should have an idea of what they were doing or trying to do. While I’m not one for planning out appearances of every major faction in advance, knowing what everyone wants means you know when someone from their roster dropping in makes sense. Similarly but perhaps more obviously, if they really don’t like what the characters are doing, they should probably get themselves involved. This does depend on power level a little, but I go with the standard axiom that the longer a campaign has gone, the more everyone cares about what the characters are doing.

The problem resolution phase has a special case that we all use, which is prepping for session one. There is not yet a ‘resolution’, per se, but you need to set the stage that explains how you get to your problem statement. As there are no resolved elements, yet, you can just make this up! Sounds freeing, but that’s how we get to “you all meet in a tavern”. There are a few simple ways to set up a first session, but I highly recommend having a session zero and just asking your players how the characters all know each other. Generally speaking you have more leeway but fewer ideas for session one, which means you have to do more thinking and less prepping for developing the problem statement.

Problem Statement

The problem statement is the part where every novice GM thinks the prep goes. It does not, there is very little prep here. The problem statement is the first part of the session, and depending on your personal preference for narration, you may say something directly to your players:

“After [the events of last session], you are all back in [place]. [Character], you’re contacted by [NPC]. It turns out that [piece of information the PCs will act on].”

How often should you actually do this? Well, not very often. In session one, sure, if the party isn’t pointed in the same direction you might need a call to action. When there are already things going on, though, it may not be up to you to provide the problem statement. Alternatively, when you do need to provide a problem statement it may be to drive multiple sessions of play involving multiple conflicts across multiple problem spaces.

Ultimately this is why Burning Wheel, to give an example, is so easy to GM. The entire problem statement section of your prep involves reading your characters’ Beliefs and writing based on that. Next tier down from Burning Wheel is something like a PbtA game; Apocalypse World has its Threat Map, a graphic organizer of all your relevant problem statements, and as long as you take good notes about which Threats you’re hitting when you can keep the game going without much additional prep. Sandbox games can usually give you one gigantic problem statement which will last an entire campaign; both Electric Bastionland and the West Marches campaign style provide this. In a trad game, without any of those sorts of plotting frameworks, you have to provide the problem statements and that means you have to write them.

The reason writing plots and problem statements is in session prep rather than campaign prep is because you do not have enough information to write an engaging conflict for a game before a single session of play. Unless your players have the charisma of leaf piles and are content to be dragged around by your prompts, any broad narrative you sketch out before play begins will be destroyed by the end of session one. Some problem statements are big enough and general enough for an entire campaign, but those are so big and so general that they’re almost always embedded into the rules of the game (Electric Bastionland is again a key example). Even if you know that your players have a massive debt that must be repaid, there’s a ‘how’ that goes to that ‘what’.

You will have to provide somewhere to start. As good as character creation in Electric Bastionland is, none of those Backgrounds or their attendant details are going to come alive at the table until you start providing the setting around the characters. Part of that work can be shared with your players, of course: nothing’s set in stone until you say it is, and starting the game by asking players leading and open ended questions is a wonderful thing. Some of this can happen in session zero, of course, but even after that your player ideas, inputs, and visions will help make your setting more real and help your players engage with the setting (which will be producing much of your narrative, so encourage that as much as possible).

But, at a certain point, certainly at the beginning and probably a few times in the middle, you’re going to end up in the setup from the top of this section: You present your players with a piece of information and they choose how to act on it. Now, the secret here is a nice splash of meta-gaming: Your players want to play the game. If they don’t know what to do and you present them with something to do, they’re going to do that thing. For that reason, this is something you pull out when your players are stalled, not when you’re not sure what’s going to happen next.

Even if you’re not spoonfeeding a problem statement to your players, you should always be aware of what the active problem statement is. You’re running the game, so it stands to reason that you should understand what it is your players are trying to do with their short term actions. You broadly have control over that ‘what’: You control all the non-player characters, factions, monsters, and forces of the world which could possibly stand in the players’ ways and force them to overcome obstacles put in their path. Given the constraints of your setting and genre, the ‘what’ has an almost limitless palette. How you use that is up to you; I’m just telling you how I prep, not whether or not to be a killer GM or a capricious GM or a ‘fair’ GM. You have that power, use or abuse as you see fit. If you want to be a good GM, though, you must go into your prep understanding that you have no direct control over how the characters choose to solve problems or the consequences those problem solving methods will create in a consistent world. To let those chips fall where they may, you need to prep your problem space.

Problem Space

The problem space is your gameboard for the session, and the sheer volume of possibility is exactly why so much of role-playing happens in the most contrived, uninspired, and stifling problem space you can imagine: a dungeon. Dungeons are easy problem spaces because they have walls, a finite number of doors, specific monsters either in specific locations or on specific schedules, and specific, countable challenges and rewards which can be encountered in an order constrained by the layout of the dungeon. In case it wasn’t obvious, I find dungeons quite boring. The problem with leaving the dungeon, though, is that as you get into bigger and more complicated problem spaces, they become bigger and more complicated to prep. The solution, then, is to prep less of them and make things up off the top of your head.

The way you prep your problem space is by doing a combination of background prep and problem-specific prep. Background prep is stuff that you could do prior to the game starting, though whether or not you do comes down to personal choice. Whenever you do background prep, though, it’s important to take notes because this is the sort of stuff that will come up again. We’re talking location notes, maps, relevant faction information, anything that is happening in the world regardless of whether or not the characters are interacting with it. That bit is why you don’t necessarily need to do much background prep prior to game start, because not only have the players not seen any of this prep but you don’t know what they’re going to be drawn to. If you write an entire faction of rogue accountants for your steampunk city and your players don’t care, the two hours you spent could have been thirty seconds. This is why in the last article I basically said to prep as much as is fun. Other than the information that’s literally part of the campaign pitch, there is no advance campaign-level prep required (indeed explaining why the last article was ‘vague’).

Once you’re running a session, though, you need to know everything that that session will touch. Your characters, for example, take a job where they need to pick up a box, not open that box, and deliver it to a dropoff point. Where are they picking up the box? Where are they dropping off the box? How many different ways can you get the box from point A to point B? Do the characters have a vehicle already, or will they need to acquire one? Who do they need to talk to along the way? Already, there’s a lot of information that you might need. You can see where the background prep is coming in: Many of the questions about where the box is coming from and going to may be tied into locations you’ve already prepped, maybe places the characters have already visited. It’s possible that one of the NPCs the characters are interacting with is someone they’ve met before. This background prep is important, and what happens during this particular job will affect these elements and how they come up later (this is why running a session involves taking good notes, or at least writing good summaries). The problem-specific prep, though, is where you can only do so much. The ‘characters deliver a box’ example is a good one because we have an obvious split between what the GM expects the characters to do (deliver the box) and what we as genre-savvy Cannibal Halfling readers know the characters will actually do (open the box). Now, no GM would be dumb enough to run this scenario without assuming that the characters will open the box, because an RPG is a playground and self-control can be turned off until you go back to work on Monday. And that is why every GM knows that they need to prep what’s in the box, and what’s going to happen when the characters open the box. It starts spiraling there, though. What if they panic and destroy the item in the box? What if there’s a car chase and, by virtue of your background prep and a freak bad roll, the box is now in the harbor? What if one of your characters was remembering a thread from a previous session and, unbeknownst to the rest of the party, sets the car on fire for insurance money with the box inside? When you are prepping your problem space, you are not prepping a hedge against every weird eventuality of player behavior. You are prepping a space where everything behaves according to certain rules, and according to those rules you can then react to events as they occur. A person told the characters not to open the box; this person has a personality which will shape their reaction. Certain things happen when someone lights a car on fire for insurance money; this cascade of consequences will unfold in a relatively orderly manner and play will emerge from these events.

The other part of prepping your problem space is getting your play aids in order. Random tables, generators, maps, and other pieces of inspiration may fall into background prep (or the creation of them may fall into background prep), but part of prepping a session is conducting a mental inventory of what you want close at hand and how everything will fall into the session. At the very least, you’ll want whatever documents you use to track problem statements and problem resolutions and the documents you use to build up your problem spaces, be those maps, flowcharts, or just good old notes. Array your prep in whatever way you want, and hopefully you’ll have all the information you need close at hand when it comes time to pull something out of your ass.


How I prep a session really does boil down to three things. What happened last time? What are the characters going to do this time? What do I need to know in order to run the game that emerges from the characters doing that thing? I don’t really have many frameworks and for the most part I don’t do anything too special either. My session notes are mostly written after the fact in summary form, and I am not too proud to admit that my players tell me when I’ve forgotten key details. For actually prepping sessions I keep all of my campaign information in the form of one long notes document (not ideal but eh, sue me), a dramatis personae, a character keeper (all pertinent stats, inventory, abilities, etc in one place), and then whatever maps I feel like keeping (both of my last big campaigns, Twilight:2000 and Cyberpunk Red, used maps built up in Google Maps/Earth). I also have a bunch of pregen stat blocks (for someone who loves GMing I hate statting out characters and for the most part I won’t do it) for randomly throwing mooks into the mix or grabbing stats for NPCs who up until now didn’t need them. Needless to say, I prefer games with less statting.

When I prep, I basically do it until I know what the characters are going to try and accomplish that session. As far as how they’ll do it or how I’ll react when it happens, I rely heavily on flying by the seat of my pants, and I like it that way. For more discussion on improv though, we’re going to need to discuss more broadly how to run a session. And that’s the plan for the last installment of How the Wonk GMs!

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