A couple of years ago, then Pixar storyboard artist Emily Coats tweeted pieces of advice on making stories that she had picked up from working with Pixar, which were later compiled on in several places on the internet, such as this io9 post. Later, Dino Ignacio created image macros of the individual rules which I am using in these posts.
Rule #5: “Simplify. Focus. Combine characters. Hop over detours. You’ll feel like you’re losing valuable stuff but it sets you free.”
I’m going to focus in on the “Combine characters” bit, because NPC generation can be a huge chunk of a GM’s prep time and it’s often not spent wisely. There’s a school of thought that says that you should fully populate each part of your setting with detailed NPC’s. If the PC’s need, say, a new horse, you should be prepared with a stable master who has a name, personality, backstory, and stat block (in case the PC’s decide to just rob them). And that goes for any other role in the village that needs filling. Now, this can be useful in a player-driven game focused on intrigue, because the PC’s need to be surrounding by NPC’s with conflicting agendas so that they can be manipulated to get what they want. It’s also a good idea to prep NPC’s ahead of time if you’re not comfortable improving characters out of nowhere. At the same time, that’s a lot of work put into your setting and the players are only going to see a fraction of it.
Consider this scenario: A noble wants to contact the PC’s in order to acquire their services, and it doesn’t make sense for said noble to meet with the PC’s directly out of the blue. You could send a messenger to the PC’s, but that’s another NPC to flesh out that the players are likely to ignore (unless you don’t flesh them out, in which Murphy’s Law applies). Or, you could have the messenger leave the message for the PC’s with the tavernkeeper that they’ve already interacted with, which not only saves you the trouble of coming up with a new character, but also gives you an opportunity to portray the tavernkeeper more, making that character more memorable and more likely to stick in the player’s minds. Obviously, you don’t want to have one NPC mysteriously responsible for everything the players need, but maybe that server who works in the tavern at night works at the stables during the day breaking horses. Maybe the town’s blacksmith also cures meat and sells it to travelers. The more use you can get out of a few NPC’s, the more memorable those NPC’s will be for your players.
A concrete example from a D&D game I ran once: The players, successful revolutionaries who had been politely asked to move on so as not to complicate the process of setting up a new government, had traveled to a different region and had agreed to help the ruling powers, who had something the players needed for the overarching plot, put down a bandit group. When the players went to infiltrate the bandits, I decided they would run into one of their former compatriots who was now working for the bandits. This saved me the trouble of making a new NPC, sure, but it also allowed me to highlight the dissonance between what they had been doing (overthrowing a repressive regime) and what they were now doing (helping another regime). It also gave me an excuse to skip to having PC’s work their way up in the bandit’s organization to meet the leaders, because I had a bandit who already knew and trusted them, and could vouch for their skills. It simplified the entire process of getting the players into contact with the bandit’s chief while serving a story point.
This goes for player backstories as well. If you introduce three new NPC’s in your character’s backstory with each paragraph, your GM’s going have trouble keeping them straight, and furthermore is going to have a hard time telling which characters you are interested in seeing again and which ones are just there because you thought they had to be there. Simplify and focus on a few characters who have an interesting relationship to your character, or who would put your character in a narratively interesting position if they resurfaced.
The same principle should be applied to plotting out the game’s story arc in general. Telling the players that they need to recover “The Five Stones of Akanor” to defeat the villain might sound good in your head, but do you want to have to do five dungeon crawls/negotiations/heists before they finally get to interact with the antagonist again? Maybe there are only three Stones of Akanor. Maybe they are all in the same place. Resist the urge to pad out your game with busy work to obtain plot coupons. Speaking as someone who has had far too many games run long and then peter out, reaching the climax too soon is better than taking too long. Better to have a game that ends up being a tight short story than a game that turns into The Wheel of Time.