D&D 5E Advice on How to Run a Megadungeon Game

[generic]

Apologies in advance for posting two threads in such a short time span.

Can any DMs with experience in running megadungeons offer me any insight? I have run mostly open-space with scattered dungeons in my campaigns, often utilizing large open spaces, and haven't really incorporated any megadungeons in my campaigns before.

What are the most important considerations when planning a megadungeon game?

To be specific, I am concerned about the following factors:

- How must a megadungeon be themed? Is it feasible to have a consistent theme in a megadungeon? If so, how, and, if not, what is the best method of theme variation?

- How can a plot work in a megadungeon environment? And, how must factions be organized in such an odd environment?

- What is a good way to justify the existence of a megadungeon?

Along with all others associated with running a megadungeon-style game. I want to create a truly great megadungeon for my players, and I would appreciate advice on both how to create the sheer level of content and how to run megadungeon games.

 

[Fenris-77]

I'm going to recommend Angry GMs Megadungeon Monday series. He gives legitimately great advice.

 

[Hussar]

I do loves me mega dungeons. One of the proudest times I have of running D&D was the World's Largest Dungeon. So, I've been where you are.

So, to answer your questions first:

- How must a megadungeon be themed? Is it feasible to have a consistent theme in a megadungeon? If so, how, and, if not, what is the best method of theme variation?

A consistent theme for the whole mega dungeon? It's possible, but, I don't think you have to go that way. In the WLD (World's Largest Dungeon), I set it up as an escape from prison campaign where the PC's needed to survive long enough to get out. But, that being said, every section of the WLD was themed differently. There was the watery section, the demony section, the maze section, the really, really stomach turningly living section of the dungeon and so on. So, I think you can have a general theme - Undermountain, Underdark, whatever - but, each smaller section, likely defined by monster CR as much as anything, will suggest themes for that section.

- How can a plot work in a megadungeon environment? And, how must factions be organized in such an odd environment?

I am assuming that the PC's can leave your mega dungeon - they can come and go repeatedly. With that assumption, I would suggest you set mission goals for the PC's. Not just "kill everything", but, things like, "rescue so and so who has entered the dungeon but hasn't come out" or "retrieve this or that macguffin", things like that.

Now, as far as factions go, there's all sorts of things you can do. Obviously, tribal groups are an option - the goblins live here, the orcs live there, the troglodytes live over there. But, also, religious groups (see Module B4 The Lost City for an EXCELLENT treatment of this), cults, and whatnot.

I think what you generally end up with is this group controls this region, that group controls that region, in between those regions is largely no-man's land where critters prowl. I found it helpful to color code my maps with different factions controlling different regions, so I could keep them all straight.

- What is a good way to justify the existence of a megadungeon?

Well, there's all sorts of stuff here. Is your mega dungeon excavated or natural? Planar or mundane? D&D has all sorts of digger critters - purple worms, umber hulks, bullettes, that sort of thing, that make the existence of a mega dungeon pretty easy to justify. Corpse of a dead god? Test from the gods a la the Magi anime? Giant lava tubes. Immense crypt. The possibilities are endless.

Few other tidbits that might help you:

1. Get information into the player's hands ASAP. If they capture someone, let that someone sing like a bird and info dump. Drop maps (or map fragments) as parts of treasure. Friendly inhabitants pass along information. The more information the PC's have, the more they will engage with the dungeon.

2. Add verticality. One of the mistakes of the WLD was that the dungeon was almost entirely flat. BORING. Chutes, slopes, ledges, anything that gets the scene 3D is a good thing.

3. Make a random table of room effects - cold, warm, that sort of thing. The whole dungeon dressing section from the DMG. Really helps.

4. Put encounters outside of chambers. Again, one of the failings of the WLD (and, I'm learning, Dungeon of the Mad Mage) is that you almost never have encounters outside of rooms. So, the PC's wander from room to room, and there is so much dead space (and dead time) as they wander down empty corridors. There's a room with 10 kobolds? Have half of them coming out of the room as the PC's turn the corner. That sort of thing.

5. If you really want to increase difficulty, start keeping careful track of lighting and lines of sight. It's shocking how short range everything gets when you're using torches and it makes for REALLY challenging fights when half the time the PC's can't see the baddies.

 

[Fenris-77]

To the above, allow me to add the idea of gating. You want to inculcate a legitimate sense of accomplishment as the players progress, and unlocking the series of magic doors, activating the portals, or whatever, are a solid way to get that done. it also helps keep the PCs mostly out of spots you don't want them in right away and at the same time giving them a legitimate goal. AGM goes into this in some detail in the series I recommended above.

 

[Charlaquin]

I'm going to recommend Angry GMs Megadungeon Monday series. He gives legitimately great advice.

It’s too bad that project is likely dead (even if he won’t confirm it). He did get through most of the parts that generated useful DM advice, but it would have been cool to see the finished map.

 

[Celebrim]

Apologies in advance for posting two threads in such a short time span.

Can any DMs with experience in running megadungeons offer me any insight? I have run mostly open-space with scattered dungeons in my campaigns, often utilizing large open spaces, and haven't really incorporated any megadungeons in my campaigns before. What are the most important considerations when planning a megadungeon game?

Buy in from your players. The main advantage of the megadungeon format is that it allows you to organize a haven/delve format that can accommodate many players, not all of which need be available on a given day. A pure haven/delve format has the rule that you always return to the surface at the end of the session. But even if you don't want to have that constraint, what you do want to have is a group willing to spend a whole campaign on what is essentially a single aesthetic of play - dungeon delving.

How must a megadungeon be themed? Is it feasible to have a consistent theme in a megadungeon? If so, how, and, if not, what is the best method of theme variation?

You can theme it however you like, but you will want to have as much variety as feasible because you're already tightly constrained by the fact that you are in a dungeon environment. So I would not suggest doing everything to a single theme. You can and it's not hard - a massive catacomb beneath a city will suffice - but it is likely to get redundant in play. Instead, you'll probably want to have several different dungeons that have grown together over time. The classic layout is a Ruins above a Basement which leads to Caves, Vaults, Mines and so forth. Then you have one or more factions which have colonized and repurposed a portion of this area, or if the caves are large enough, have perhaps been living there all along. But any combination is possible depending on what you want to do.

How can a plot work in a megadungeon environment?

If you have a plot, typically, your hook is set and your plot driven by the interplay of factions on the surface in the Haven. Often there is a Foozle that needs to be recovered, or there is an Ancient Evil that someone wants to awake, or there is a Portal to be opened, or what have you. And in a simple version you have one faction that is trying to do something and another faction that wants to stop them. The basic twist is to have the players initially working for one faction, only to discover that they have been deceived entirely about the motives of that faction.

You can also have factions in the dungeon, but I find that this is less reliable. You never really know if the players are going to care about allying themselves with anyone, and the factions in the dungeon are realistically going to tend to have somewhat alien and private motives. But if you have a cave themed dungeon, you can always have a faction of potential allies deep within it, be it svirfneblin or myconids, whose goals will align with the players to some extent.

What is a good way to justify the existence of a megadungeon?

There are a number of realistic underground constructions of large size - quarries, mines, catacombs, sewers, basements, viaducts, etc. There are even real world underground cities historically, and of course more so in a fantasy setting. There are also many sorts of caves, from ice caves to lava tubes. So you just put a few together - a cursed city that has been buried under the ice for a thousand years. Or they mined too deeply and broken into an ancient cavern where foul things lived. Or whatever. Come up with some ideas and I can help you justify them. It is afterall a fantasy world.

Along with all others associated with running a megadungeon-style game. I want to create a truly great megadungeon for my players, and I would appreciate advice on both how to create the sheer level of content and how to run megadungeon games.

Honestly, in ratio of time spent in creation to play time, running a megadungeon is probably one of the easier things a DM can attempt. While the up front costs can be enormous,you can get a heck of a lot of play time out of a dungeon in the long run. It's much more efficient in the long run than running smaller dungeons, detailed plots, event based scenarios, and so forth for a given level of quality. The real trick, and this is the rub, is you have to be really spatial and good at mapping. A really good layout takes a lot of work. If you aren't completely confident in your mapping chops, I'd strongly suggest you spend a lot of time playing with random generators, both those available online and the one in the back of the 1e AD&D DMG. While neither is good enough to just random up and go with, you will get a lot of ideas and a good sense of what you can do to add variety and interest to the map. If I could sum up a good map in one word it would be, "Asymmetry." Force yourself to avoid symmetry, and come up with reasons why left is different than right and back from front.[/QUOTE]

 

[Fenris-77]

It’s too bad that project is likely dead (even if he won’t confirm it). He did get through most of the parts that generated useful DM advice, but it would have been cool to see the finished map.

Yup, it's a shame. As you say though, the bulk of the design advice is there, and that's really what I'm indexing. I would have liked to the see the map too.

 

[Shiroiken]

First and foremost, make sure your players want to play in a megadungeon! I've offered up several megadungeon adventures, and my players have passed on all of them whenever they've had the choice. It's not always the most interesting concept for players, so get input from them first.

I like the multi-level idea over the segregated concept. In the segregated concept, the players cannot access parts of the dungeon until they perform part of the plot device/mcguffin, because they're not high enough level. In a multi-level dungeon, the general concept is the deeper you go, the more dangerous it becomes. If the players choose to (or are forced to) go deeper than they are ready for, they'll need to be ready to run!

Overall when designing a megadungeon, first consider the purpose of the dungeon. Next, you should consider having multiple levels of the same depth, with limited connection between the two, giving the players choices on where the explore (also giving you an out to add levels as needed). Most areas should be empty, with maybe the occasional exploration challenge, as monsters would generally congregate in groups. Finally, make sure you have plenty of options for movement, including multiple entrances, and quick passage to lower levels (once the party gets higher level), since a megadungeon will normally consist of numerous expeditions. Traps should make sense, both from a design perspective of the original intent, plus the movement of the occupants (some traps should have already triggered).

Monster politics can be tricky, because a lot of players, especially newer ones, tend to charge headlong into combat before any negotiation can occur. Easiest solution to that is to have the intelligent monsters subdue and take prisoners. Humanoids would constantly war with each other over resources, especially food and water. Other intelligent monsters might have other motivations, including revenge, greed, or just malice. Alliances between the factions can be made and broken, and the PCs would become a wild card in these events that each faction would want to control.

Example (from my last campaign)
There was an ancient hill dwarf stronghold that had long been forgotten to time. The above ground sections (mostly used for meeting with other races) had long since fallen to ruin, but within a standing structure was a set of stairs that lead downwards. The party knew nothing of the history of the stronghold, and part of the plot was learning the history of it (there was an Indiana Jones type sage, plus a dwarf in the party).

The first level consisted of a formal throne room and supporting rooms, such as guard chambers, kitchens, dinning, etc, but most of these were long unrecognizable. The monsters inhabiting this area were beasts that had wandered in from the outside, subsisting on fungus and moisture that leaked in from the surface. There were also a lot of traps, which were activated from a secret chamber behind the throne room (in case the stronghold was ever attacked), and the traps were activated until the party found the mechanism. Finally there was a deep well that led to level 6, which was currently the lair of a black dragon.

Another area on the same level was accessible through a secret door (other accesses had collapsed, but indicated it was there). It was originally the primary garrison for the stronghold, including the armory and several hidden chambers for diplomats and others VIPs to hide in case of attack. This area had mostly been taken over by a kobold clan, but there were various other monsters that preyed upon them. The kobold clan was currently at war with the goblin tribe that lived on the level below (connected to both areas of level 1), who periodically raided them for food (the kobolds hunted the various beasts in the other area). The party decided to exterminate them, because in their first encounter they killed one of the PCs.

The second level was originally more garrison space, plus storage for supplies. There was a secret exit outside, to be used for evacuation and for importing large goods. The supply area was controlled by the goblins warring with the kobolds of level 1, and the stairs up to the beast section of level 1 was controlled by orcs (who also hunted there). The exit section, which also had the stairs down to level 3, was controlled by a group of ogres that demanded tribute to use either. The party could ally with any of the groups except the ogres, who desired the status quo remain (as they benefited)

The third level was intended to be the main city of the dwarves, with several area, each controlled by various monsters, but I never got this far in my design. The players stopped after killing the kobolds on level 1, so I abandoned the project.

 

[Fanaelialae]

My limited experience with running a megadungeon is giving each level a theme.

My players seemed to enjoy the one I ran. In fairness, it was optional side content to the campaign, which was more sandbox style. With the first party, they delved a few levels into it but were more concerned with goings on in the overworld. However, when they retired the party around level 11 (the druid had discovered a sacred grove and chose to protect it full time, and the rest of the party decided to help him so they retired too), the players brought in a new group whose primary motivation was to fully delve the dungeon.

It was a living dungeon. When they discovered it, they were told (by a monk who was keeping an eye on it) that it seemed to be growing and that sometimes monsters would emerge to snatch people.

Each level had a different theme. The first one was pretty standard fare. An ogre overboss and his minions. I think the next level had weird, mutated goblins with crystals growing out of them. I tried to make each level a little weirder than the last.

Every few levels (3 maybe?) they would discover a secret staircase that lead all the way up to the entrance (this was important so that they were not constantly tediously retreading old territory - some of that is good but you don't want getting to the latest level to take longer than exploring that level). For these earlier levels, it was sufficient to find the staircase down, although a boss was usually guarding it.

Eventually, they reached a point where the dungeon levels were fully realized demiplanes. In one they had to break a three way standoff between dragons that were preying on a tribe of centaurs. In another, they had to deal with the genie leaders of 4 unfriendly elemental factions. For these later levels, a magical key found in that level was required to progress to the next.

Eventually they made it to the final level, and discovered the source of the dungeon to be a nascent seed left over from Creation. It was only quasi-sentient, and was blindly flailing about trying to gather the resources to be "born" (which in this case was sentient minds from which to draw ideas). The result of which was the dungeon. The players had the option of slaying it (in which case they would have each received a Wish from the remaining energy) or helping it by telling it what to create. They chose the latter and created their own little sliver of the multiverse. The option was there to travel to their new world and explore it, but they chose to remain in their original world and undertake overworld adventures.

 

[LordEntrails]

A lot of good input here. The only thing I will reiterate is not to gate the levels or danger. IMO, one of the big things of a mega dungeon is the characters have to know they can get in over there heads. Stupid characters end up dead. It's part of the "charm".