The fun of inventing new societies, creating entire civilizations, and developing cultures is what draws me to storytelling, at least when it comes to what I get the most from. As a result, I really enjoy playing Dungeon Master and one of my favorite parts of running my own Dungeons and Dragons campaigns is the prep work. The thing is, preparation work, especially world building, is one of those things that will take exactly as much time as you’re willing to give it. One of the most important lessons I’ve learned as I’ve practiced storytelling, both as a writer and a dungeon master, is that there’s a fine line between over-preparing and creating a world that doesn’t feel real.
One thing that dungeon masters often need to do is create towns and cities for their players to encounter. If it is a sizable city, chances are good that there are multiple blacksmiths the players could hire to create them some new gear. Some of them might be better than the others, some might have a preference for particular kinds of work, and some might just hate adventurers. They all have names, pasts, business practices unique to their specialties and levels of experience, and they all have opinions about each other and each other’s work. You, as the dungeon master, can figure all of this out or you can spend the time working on the political situation that it is likely the players will encounter instead of the intricacies of business and the people behind said business that will mostly be ignored by the players who only want to know who the best smith is (which is usually easy to figure out). To be entirely fair, some players might be more interested in the business scene than the political one, so maybe that’s the system that’s more important to your next session. Or maybe they won’t be interested in either the business or political situations and will just want to kill some monsters and protect some peasants, so maybe you should spend more time focusing on the environment around the town.
The key to figuring out what you need to prepare the most is in figuring out what your players will want. I’ve never met a player who changed what they were interested in from one session to another aside from one player who was literally just doing it to point out the holes in the world and ruin everyone’s good time. All players, even the aforementioned asshole, tend to be very consistent. Your first few sessions with a new group might need a little more work because you’re not sure what they’re going to care about yet, but once you’ve gotten a feel for them you learn where you need to focus.
The way I view dungeon mastering is that I’m basically creating the world only about as far as the next few steps ahead of the players. There’s always a horizon, major geographical features, and a sense of society behind it all, but the majority of the world is an empty canvas I only fill in as the players move or discover. If you wind up preparing in the wrong direction or keep trying to push your players in the direction you want them to go in, they’re going to wind up walking into all of the blank spots and feel like the world isn’t as solid enough to really believe in. Some players are more willing than others to ignore the empty spots they find, but most of the reason most people play Dungeons and Dragons is for the immersion you can achieve when you set aside the concerns of the primary world and fully embrace the secondary world. These are the people I run for and this is the kind of player I am.
No matter what you do, there will always be hiccups. You can’t have every name ready and planning everything out in excruciating detail so you’ve got the name of every blacksmith and item shop proprietor prepared is a quick recipe for madness and frustration when 99% of it winds up going unused. I’ve even seen dungeon masters get angry with their players for not exploring and caring about the world as much as they did. I’ve even felt it myself, when I took the time during the week leading up to the session to prepare an exciting encounter and a new bit of the world for them to experience and then my players spend two hours dithering about who goes on what errands and what supplies they need down to the last copper.
It can hurt to put in a lot of work and not get to see it come out in your game session, even when you know it’ll come up in the next one or the one after that. It doesn’t hurt much, though, so long as you focus on making sure there’s plenty of world for the players to experience as they dither about and shop for really weird things you’d never have imagined they wanted. Really, it just give you a week off of preparation. If all you can see is all the work you’ve done going unnoticed or un-experienced, you’re going to eventually lose your temper.
Part of the problem is how the line between too much and not enough shifts from group to group and even from session to session. My players care a lot more about the names of the people around them if they know they’re going to be in the same place for a while. They also tend to care less about the actual layout of the town the longer they’re there or the bigger the city is. For over two years, they’ve gone through literally the same town every time they enter a civilized area without ever realizing that they’re all laid out the same. All I’ve had to do is scale it up based on how many people live there. I created my second city just recently because I needed something different for a future adventure they’re probably going to go on. They don’t care what the places look like because they’re more interested in the people and the plot than the exact geography, which works for me since I can create interesting characters with ease and I’ve got a list of random names sorted by race and status so I don’t need to spend any time trying to figure them out when I make up a new NPC for them to befriend/eventually fight.
If you’re trying to figure out where the line is for your group, I recommending starting with more detail and slowly scaling it back. That way, you can avoid subjecting your players to a campaign full of blank spots before you figure it out. Step it down slowly and you should be able to notice when your players start to feel like the world isn’t as real as they’d like. At that point, kick it back up a little bit more than you think you need to and work to achieve a level of effort you can still enjoy. You’re supposed to have fun, too.