Let’s Build a Low-Prep Megadungeon: Part 5
It‘s All Connected, Man!
Welcome back, fellow dungeon builders! When we lasted delved into our creation, we fleshed out the upper levels of the dungeon with factions, and then gave the factions various routines to ensure the place felt alive to the player characters. This time, we’ll start talking about what comes after the party has bested their first couple of challenges. That’s right — we’re going to map out the rest of the megadungeon so we know where the party is headed, and what they’ll face when they get there!
“Whoa, whoa, whoa” I hear you say. “I thought this was a low-prep megadungeon. Mapping all that stuff out sounds like an awful lot of prep!” You’re right — mapping out and populating a bunch of dungeons our players will never visit does sound like a lot of prep, which is why we won’t be doing it. Instead, we’re going to build a very basic map, just so we have an idea of where the party might end up, depending on which path(s) they take. Then, as the PCs make their way through the dungeon, we can start to flesh out the places they actually get to.
Think of it less as a map, and more as a flow-chart (spoiler alert!).
Before we start planning the rest of the dungeon complex, I want to take a minute and discuss how a megadungeon differs from a regular campaign. A standard campaign tends to be a series of linked adventures — discreet sets of encounters which the party ventures (or is brought) to, and in between they rest and recuperate before moving on to the next adventure. Travel to-and-from destinations is not necessarily safe, but unless survival is a theme of the campaign, the characters can generally expect to travel with little more than random encounters to stop them.
By contrast, a megadungeon takes place in a single location, and that location (along with the adversaries within it) is actively trying to kill them. Caves are dangerous; ruins are filled with traps and undead; dungeons contain portals to the dark realms beyond; and these things are all connected to and by each other. Rather than well-travelled (and possibly well-guarded) roads, the passages, caverns and caves which connect the parts of our megadungeon could betray the party at any moment, which should force them to make hard choices. Do they press on with no rations, knowing they could starve before reaching a haven? Do they drop their precious loot so they can make it back to the surface more quickly? Do they chance the shortcut, even though the way is difficult and might collapse? While these sorts of choices exist in a standard campaign, they are more acute when exploring a megadungeon.
Another key difference between a megadungeon and a standard adventure campaign, is that the megadungeon his both horizontal and vertical — there’s a three-dimensional aspect to the map we, as the creators, generally don’t have to think about too much in other adventures. This verticality produces some new challenges, but also plenty of opportunities. There should usually be more than one path connecting the individual dungeons within the megadungeon, for instance, and those paths don’t have to be (and shouldn’t be) obvious. This lets us have some fun by creating the sorts of choices I described above for the party.
Also, knowing how the different locations connect to each other not only lets us more easily prep for where the party goes, but also helps us track what might change as a result of the player’s actions. If a goblin warren sits above a spider’s nest, we know the spiders might take over after the players clear the goblins out. Now, this means we have to have some idea of what each section of the dungeon is, but that doesn’t mean we have to prep them all! Again, we should only be preparing the locations the players are currently in, or about to head to. Communicate with your players — ask them where they want to go, and be honest with them when you aren’t ready for them to venture somewhere. Sometimes I might say something like “this passage leads down into the dark, and you sense something ominous and powerful beyond. You might want to come back when you are stronger” or I’ll be more direct — “Hey guys, I haven’t prepped that area yet. You can go if you want, but we’ll need to stop for today so I can get ready.”
Speaking of prepping sections — not every location needs to be a baked dungeon map. Consider what type of location the party is in, and use that to decide whether it needs a complete map, or just a random encounter. For example, if the party is traveling through a vast network of tunnels and small caverns, you don’t need a map. Let them make some survival checks to find their way, and hit them with small random encounters. Out of the Abyss, a campaign by Wizards of the Coast, has a whole chapter written like this.
Finally, give some thought to how the locations are connected — is there a clearly marked and easy-to-find passage leading to the next level, or is it a flooded cavern the players have to swim through. Does the path run down an ancient lava tube, which could collapse under their weight? Are the tunnels small and difficult to pass through? Is a magic device or spell required to travel from one location to the next? In the real world, natural cave systems are usually random and extremely difficult to traverse — spelunkers obsess over weight, bulk, and other factors before entering into caverns because they know how hard it will be to get in and out. To replicate this, I highly recommend reading Veins of the Earth by Patrick Stuart, for its excellent section on generating cave systems.
So, with all that out of the way, what does our megadungeon look like? Well, like this.
As you can see, I’ve got several locations named and ready for when (or if) the party makes their way to them. The “end” of the dungeon is at the bottom — the Overmind/Portal location. The main flow of the dungeon should move the party towards that location, but offer multiple, branching paths and optional areas. I fully expect the party to never see some of these places, which is just fine — less work for me! That being said, I do have an idea of what these areas are, or might become.
- Seashore Ruins — our “hack” of the Sunless Citadel. The party should have a couple of exits from this location to the next one.
- Flooded Crossroads — a small map connecting a few other locations. There’s a low-level encounter here, and other creatures probably use this area to traverse the upper levels. This can be a “safe” place to rest, but with a slight chance of danger.
- Catacombs/Crypts — tunnels located under the estate house itself. The path from the crossroads is easy, but long and winding, providing plenty of opportunity for excitement along the way. I think the lord of the estate had something unpleasant going on in here.
- Undulating Gardens — a mostly submerged cavern, filled with nasty sea creatures. This is an area where we can explore “mundane” weirdness, like more fish people and other underwater hazards, and also sprinkle in some hints to the evil deeper in the dungeon.
- Labyrinth/Ruined Halls — the main arteries which connect the lower and upper levels. I doubt I’ll actually make a map for this — but fill it with encounters and strange locations, instead. The players can keep track of what they find here, and double-back to some of the locations if needed. This might also be a good place to put some kind of market or NPC community, so the characters have a chance to roleplay and possibly resupply.
- Fractal Prison — something terrible is held here, waiting for the chance to escape. Maybe its the cause of the nightmares plaguing the surface, or maybe its something else entirely!
- Labs — whoever built this place was experimenting on something, and now this area is filled with abberations and abominations. Still, it’s the most direct path forward…
- Temple Complex — the heart of the dungeon. The architects came here to worship their dark gods (or whatever), and carved a sprawling complex into the living rock. Another location I probably won’t map out entirely, but fill with smaller locations and encounters.
- Enclave — other denizens of the Underdark have discovered this place, and have set up camps in this large cavern. From here, the different factions send scouts and raiding parties into the rest of the dungeon, and also make war on each other. This could provide plenty of opportunities for roleplaying and intrigue, as well as a steady supply of encounters elsewhere.
- Overmind/Portal — I don’t know what this is yet, and I don’t care. All I know is the “big bad” lives here, and the players and I can discover what that is together!
Whew! We covered a lot of ground here, but I think we’re in a better spot than we’ve ever been to run our players through a tense and exciting dungeon crawl! Using the stuff we’ve covered, you should be able to populate the rest of the dungeon yourself and make it your own. If you do, I’d love to hear how your dungeon is different than mine. I hope you’ve found this series helpful, and I wish you luck in architecting your own “low-prep megadungeon”. Cheers!
