Alexis has a great post up today about player agency, using NPCs based on behavior and motivations, and how that can, and should, define the "narrative" within a DnD game. I'm not going to attempt to personally attack Alexis here, so I hope it's not perceived as such, but he is a rather controversial figure here in our little blogging world. Most of his posts, despite what can be looked at as written with a somewhat pretentious attitude, are interesting, informative and entertaining to read. Despite his somewhat contemptuous and misanthropic demeanor in our little corner of the world, he quite often has these moments of genius which make you look back and say "fuck yeah!" and this is one such moment.
There is often this perception that the "sandbox" cannot co-exist with the "story narrative" in DnD. I believe, however, that the two are so intertwined that neither element can be successful without the compliment of the other one. The modern day RPG focuses on "paths" and "storylines" in which there are defined encounters or events that are going to happen no matter what the PCs do. These narrative railroads essentially lead the PCs down a trail where the DM is the storyteller, and the players little more than kids sitting around the campfire, listening, and maybe rolling some dice here and there.
In the sandbox, however, there are an infinite amount of storylines happening all over the place. The ones the PCs choose to get involved with, should have meaningful consequence based on the choices they make as players. Otherwise, why bother with the game? The sandbox isn't about simply going from hex to hex, or dungeon to dungeon, fighting goblins and collecting treasure. Of course, they could be, and many are, but that doesn't make for any more of a meaningful experience for a player than a railroaded storyline. At least in the storyline, interesting things are happening.
Rather, the sandbox and the story should co-exist and feed off of one another. There are factions, and people, in the world that are trying to do different things. If the PCs suddenly become a part of that, then their choices should have some consequence, but ultimately they should have the choice. And those choices might not always lead to rousing success. In DnD, just as in life, sometimes you fail. There will be moments when your PCs will do something, or not do something, which might result in some pretty severe consequences, perhaps even death for the character(s). If you utilize NPCs, especially villain NPCs based on their behaviors (rather than as a means to satisfy a story you have concocted) then you are showing the PCs a living and breathing world, one in which their actions, or lack thereof at times, matter...at least in terms of whatever plot, or story, you might have them engaged with.
Could those actions have world changing consequences? Maybe. Could those world changing consequences have a significant impact on the game? I'd say definitely. Death Frost Doom is a great example of this. If the PCs follow a certain series of choices in that adventure, they will unleash a horde of undead onto the land. We've all seen play reports on this module in which that was the case. Would that be a world changing event? Damn right it would be, and if so, let it be.
To illustrate this, I'll use an example of how I am using NPC behavior and player choice/consequence in my current game, rather than just letting an event happen for the sake of the storyline. In our very first session of my current campaign, the PCs were tasked with retrieving a certain MaCguffin. They needed to raid a thieves guild warehouse to get it. They failed in this. So what happened? The villain NPC who was trying to get said MaCguffin was able to get it before the PCs. The result of the NPC having retrieved this MaCguffin had some pretty dire consequences. Within the sewers below the city, this villain was able to unleash a horde of undead which threatened the security of the city. When the PCs managed to return, they had to fight through a group of undead to eventually find the NPCs lair in the sewers. They were, unknown to them in our last session, one room away from tracking him down. So what did they decide to do? Well, being severely depleted of resources and hit points, they decided to rest, heal some wounds, and memorize some more spells. Now, I could have the NPC still waiting on them in the next room, ritual dagger in hand ready to sacrifice a victim just as the PCs enter (that would be the case in a story driven module where player agency matters little), but the PCs made the choice to rest. The NPC knows they are there. They have severely put a dent in what he was trying to do. But if he knows they are there, he isn't going to wait in his chambers for them to walk right in and defeat him. So, in the midst of their rest, he will make an escape, and be successful. Why? Because based on the circumstances and choices the players made, this is the behavior he would illicit in response. He is, by the way, leaving behind a summoned demon from the Abyss to slow them down.
As Alexis stated in his blog post, the narrative for DnD is, and never should be, a predefined set of events. If you know what will happen in the end, why bother playing? The fun in the game is NOT knowing what will happen, and giving the players the freedom to define for themselves, through play, what their destiny will be.