Go to Part 1

In (Re-)Running the Megadungeon, we looked at how you can evolve a megadungeon over time, actively playing it just like the players actively play their characters: You repopulate it. You modify it. You roleplay the inhabitants.

In the process, you create a dynamic experience that’s constantly surprising and delighting (and terrifying) your players, while also dramatically extending the amount of high-quality playing time you can get out of surprisingly simple prep.

Now I want to return to the series, flip things around, and take a closer look at how the players can evolve the megadungeon over time.

(If you’re here because you’ve innocently just started reading the series: Alert! The last link skipped you forward in time by a dozen years! Don’t worry! Any resulting temporal anomalies will resolve themselves shortly without disrupting your personal continuity.)

INTO CASTLE BLACKMOOR

Of course, almost any action the PCs take in a megadungeon will affect its future form. This is, after all, a back-and-forth dynamic. Killing all the lizardmen is what allows the elementalist to move in and set up shop, right? But what I want to spotlight today are the cases where the PCs more deliberately (and proactively) transform the dungeon.

Most of the examples we’ll be looking at here come from the open table campaign I ran in Castle Blackmoor, the original megadungeon created by Dave Arenson in which the modern roleplaying game was invented, and from which modern D&D was born. Running Castle Blackmoor provides a deeper look into how I set up and ran the campaign, but all you really need to know for now is that Castle Blackmoor sits atop a hill and beneath it lies the dungeon.

When the PCs enter the dungeon, this is the first room they encounter:

Speaking frankly and from experience, this room is incredible.

First, it’s too large for normal torchlight to fully illuminate it. So you’re immediately thrown into a fog of war.

Second, even if you have a more powerful light source, the shape of the room means that you can never see the entire room when you first enter it, no matter which entrance you use. Whether you’re entering the dungeon for the first time or returning to this chamber in the hopes of escaping to the daylight above, you can never be entirely certain if the room is empty… or if there’s something lurking just around the corner.

Third, and most importantly, there are ten doors. (Plus three more secret doors, including two hidden in the columns that aren’t indicated on the map here.) Literally the moment a PC steps into the Blackmoor dungeon, the player is confronted by the absolute necessity to make a choice: Which door are we going to open? Where is our adventure going to take us? The DM isn’t going to make that decision for you. You’re in control of what happens here.

Even if you have literally never played a roleplaying game before (and I’ve run Blackmoor for such players), this room inherently pushes them into actively engaging with the scenario while simultaneously teaching them that the game is about the choices they make.

The entire room screams player agency, and then holds forth the promise of endlessly varied adventure (every time you come back, you can pick another door). It tells you literally everything you need to know about Blackmoor, about dungeons, and about the game in an instant and without ever explicitly explaining any of it.

Playtest Tip: Describing the shape of this room verbally is impossible. If you’re playing in the theater of the mind, nevertheless make a rough sketch of its shape and be prepared to show it to the players. I kept a copy of the sketch I made clipped to my Blackmoor maps. But I digress.

The reason I bring it up here is that it’s a really simple example of player transformation of the dungeon: Confronted with all those doors, the players were confusing themselves when discussing their options and making their maps. So for the sake of clarity, they labeled the doors: First on the maps and then, shortly thereafter, in the dungeon itself.

Starting with the door to the left of the staircase, they labeled them alphabetically, A thru J. (Hilariously, however, the group who first did this missed one of the doors, so “J” ended up out of sequence.) The doors were first labeled in chalk (which one of the PCs had purchased), and this was later made more permanent when mischievous sprites in the dungeon started erasing the labels.

In doing this, my players were unwittingly echoing what Dave Arneson’s original players had done nearly fifty years earlier: After arbitrarily choosing the northwest door, they apparently fell into the habit of using it to mount most of their expeditions. It became known as the “Northwest Passage,” and eventually one of the players hung a wooden placard over the door with this name written upon it.

A later group took this even further, making coded markings at the various stairs in the dungeon to serve as navigational aids. These codes actually referred back to the door names (so for example, a staircase labeled G2 indicated that they were on the second level and this staircase would take them back to Door G… assuming that they hadn’t gotten lost or confused and encoded the wrong information).

TANGLEFUCK

Becoming lost and confused reminds me of another fun story from my Blackmoor table.

Looking at this section of the dungeon on the map, it seems fairly straightforward, although you may note Arneson’s devilish penchant for oddly angled diagonals.

One evening, however, a group headed into this section of the dungeon and began going in loops. Their map rapidly metastasized (because they were mapping the same corridors over and over again as if they were new passages), and by the time they realized what was happening they were hopelessly disoriented. They began making navigational marks (labeling walls and intersections), but because they were already lost, most of these marks were incorrect, contradicted each other, and

Fortunately, everyone at the table was having a great time with this, laughing uproariously whenever the PCs circled around, confident they were breaking new ground, only to come face-to-face with their writing on the wall or floor. (At this point, the sprites had already begun messing with the door labels, so there was also paranoia that something was here in the hallways with them and was altering their signs.)

One memorable moment came when they arrived at an intersection, confidently declared that they had gone left the last time they were here, so they were going to go right this time and they would definitely get out! … except that wasn’t right, and so they ended up looping back around and coming back to the same intersection again.

“Okay, so we definitely went left last time, so we need to go right this time.”

They did this four times!

Ironically, the door out was, in fact, immediately to the left of that intersection.

When they finally figured this out and, with great relief, headed through the door, one of the PCs stopped, took out some charcoal, and wrote in large dwarven runes on the wall, as a warning to all who might come here in the future: TANGLEFUCK.

And so this section of the dungeon came to be known forever after.

OTHER TALES FROM THE TABLE

In another campaign I ran, the PCs began collapsing tunnels to prevent anyone else from entering a section of the dungeon haunted by a malevolent force. In yet another, the PCs memorably hired a group of mercenaries to guard the entrance to the dungeon and prevent other adventurers from entering. (An effort which met with mixed success.)

These player-led transformations are particularly wonderful in an open table: Because there are other players exploring the world who were not part of the group which made the original changes, those players get to discover (and, conversely, leave their own transformations for others to discover in turn).

These long-term interactions across multiple sessions and groups can pay off in a multitude of gloriously unexpected ways. For example, I mentioned that my Blackmoor players began encoding navigational markers. But there were actually multiple characters who had the same idea, which meant that different groups were encoding information in different, overlapping ways. And then there was the memorable group where only player had previously been part of an encoding group… and he screwed up the code. So not only did that group leave miscoded marks, but the other PCs in the group — who had been taught the incorrect method — carried that mistaken information into other groups and spread it even farther.

So who made these markings? Another group of explorers? Or monsters looking to trick the interlopers?

The fact that there are other real people interacting with this shared game world and that you can see the consequences of their actions and they can see the consequences of yours is intoxicating. (And can easily lead to motivating players to make even larger and more meaningful impacts on the game world.)

Even at a dedicated table, however, player-led transformations are great. It’s basically GMing on easy mode: You can often just lean back and take notes.

More importantly, the players are metaphorically throwing you a ball. They’re inviting you to play with them, and in the process making it a lot easier for you to generate your own responses that will continue to evolve the dungeon. (Like those sprites altering the navigational markings.)

All you need to do is pick up the ball and throw it back.

FURTHER READING
Treasure Maps & The Unknown: Goals in the Megadungeon
Keep on the Borderlands: Factions in the Dungeon
Xandering the Dungeon
Gamemastery 101

We’re one month away from Dave Arneson Day, a celebration of the Father of Roleplaying Games on the day of his birth, October 1st.

Last year I talked about the Arnesonian Dungeon and I described how I wanted to celebrate Dave Arneson Day by Running Castle Blackmoor: Seeking to recapture that moment, almost 50 years ago, when Dave Arneson’s players went down into his basement, discovered the Castle Blackmoor miniature sitting on his table, and ventured down the stairs into the dungeons beneath it.

It’s a powerful, iconic image. But the truth is that it’s not quite that simple.

My first exposure to the dawn of the modern roleplaying game came through Greg Svenson’s “The First Dungeon Adventure,” which has been revised several times, but which you can read in its most current form here. Greg Svenson played in Arneson’s original Blackmoor campaign, and his story of having “the unique experience of being the sole survivor of the first dungeon adventure in the history of ‘Dungeons & Dragons’ indeed in the history of roleplaying in general” is really cool. It captures the imagination. It invites you to really envision what it would have been like to sit at that table with Dave Arneson and discover something truly new and unique and amazing. To be there when it all began.

But it’s probably not true.

For those unfamiliar with this topic, there are several key cruxes in the early history of Blackmoor:

When the first session was played: Several key pieces of documentary evidence are widely considered to point to 1971 as the date of the first Blackmoor session. (These are not actually conclusive, IMO. They’re just the earliest contemporary documentary evidence that can be reliably dated.) This date has gotten particular weight after publication of Jon Peterson’s Playing at the World, an incredibly authoritative treatment of the early history of RPGs, because Peterson virulently rejected all eyewitness accounts in favor of contemporary documentary evidence.

(Peterson has good reasons for this: When Gygax attempted to claim that AD&D was a game unrelated to D&D so that Dave Arneson didn’t need to be paid royalties any more, Dave Arneson sued him. As often happens, the ensuing legal battle separated everyone involved into two distinct camps and created disparate narratives about what “really” happened which became entrenched. Once that happened, virtually all eyewitness accounts were irreparably tainted. You get the same thing in another case with Gygax, who miraculously starts claiming that he never liked Tolkien that much and his work wasn’t a significant influence on D&D at exactly the same time that TSR got sued by the Tolkien estate.)

However, in their earliest accounts virtually all of the Blackmoor players cited 1970 as the date of inception. Although several people, including Arneson, later decided that their memories must be faulty after looking at the documentary evidence (further muddying the waters), the most significant testimony is that of David Fant: He was the original Baron of Blackmoor and infamously became the first vampire. As such, he definitively played in the earliest sessions of Blackmoor, and yet he stopped playing when he got a job at KSTP at the end of 1970 and definitely was not playing with Arneson in 1971. (The fact he can definitively date the event which caused him to stop playing with Arneson lends his account substantial credibility.)

What the first session actually consisted of: The three main variations of the tale are the dungeon crawl (“we came in, there was a model of Castle Blackmoor in the middle of the table, and we started exploring the castle’s dungeons instead of playing the Napoleonics game we were supposed to”), the troll under the bridge (related in a fanzine and also attested to by players as being the first use of Chainmail), and the “rescue Dave Arneson from a plane crash in Europe, go through a cave, and emerge into the world of Blackmoor” (in which everyone was playing themselves and only later transitioned to a form of the campaign where they were playing different characters).

Who actually played in that first session: Even once you get past the question of what was in the first session, there’s a significant disagreement over who was there.

What were the original rules: Did the original Blackmoor use the Chainmail rules for combat or not? This is incredibly complicated by the later TSR vs. Arneson lawsuits where the question of whether or not Arneson’s game was derivative of Chainmail was legally significant.

To give a small sampling:

David Fant says he was at the first session, it was the “castle in the middle of the table instead of Napoleonics and we went into the dungeon” variation, and Dave asked him if he wanted to be the Baron of the castle.

Bob Meyer says he was at the first session, it was the “troll under the bridge” scenario, and it definitely used the Chainmail rules because he died in one hit as a result, declared he thought the game was terrible, and refused to play again for several years.

Greg Svenson says he was at the first session (later revised to be the “first dungeon adventure”), it was the “castle in the middle of the table instead of Napoleonics and we went into the dungeon” variation, and it involved Baron Fant being an NPC (which clearly contradicts Fant’s account).

To be clear, I’m not saying any of these people are being deliberately deceptive. I’m saying these things happened a long time ago, and it’s also quite likely there were many people who played in what they thought was the “first session” of the game without being aware that Arneson had run stuff in the Black Moors before that, and there are also all the foibles of an inconsistently shared communal narrative PLUS the complications of the Arneson vs. Gygax feud and legal troubles.

If you’re interested in delving into this lore more deeply, check out the aforementioned Playing at the World by Jon Peterson. A documentary called Secrets of Blackmoor has also just recently been released. Although I found it to be a somewhat flawed work when I attended the world premiere, it nevertheless affords you the irreplaceable opportunity to hear these stories from the lips of the people who were actually there.

And start planning your celebration of Dave Arneson Day now!

Go to Part 1

The creative and evolving process of restocking a megadungeon is something I discuss at length in (Re-)Running the Megadungeon. I’m not going to rehash that material here, and if you’re unfamiliar with that earlier essay you might want to take a few minutes to peruse it.

As I’ve mentioned in the past, I find that the process of restocking a dungeon is as much art as science: You want to look at the context of how events are evolving within the dungeon — the actions the PCs have taken, the responses NPCs have to those actions, and so forth — in order to determine how the dungeon will evolve over time.

With that being said, I often find it rewarding to incorporate random procedural content generation. It can prompt me to pursue unusual creative directions and force me out of my comfort zone. It can also “force” me to put in the work when it can sometimes be easier to default to “nothing happens”. For example, at the beginning of every session in my OD&D Thracian Hexcrawl I would check every dungeon lair that had been previously cleared out by the PCs with a 1 in 8 chance that it had been repopulated. This “forced” me to revisit areas that I might otherwise have left fallow.

For Castle Blackmoor I could have easily just used my standard procedures for megadungeons: A kind of instinctual “feel” for each section of the dungeon, combined with on-demand procedural content generation checks or creative inspiration for restocking each section. (I, personally, draw a distinction between game mechanics and procedural content generators: Although they can be superficially similar, I think their function in the game is quite different. One way that this manifests in my campaigns is that I consider mechanical results binding; they can’t — and shouldn’t! — be fudged. Procedural content generators, on the other hand, exist to prompt creativity and, because they’re not mechanics, they’re not mechanically binding. But I digress.) Since my design goals for Castle Blackmoor were explicitly about exploring an alternative to my typical megadungeon procedures, however, I thought it made sense to take a closer look at the restocking methods I would use with the dungeon.

As far as I know, however, Arneson never explained his restocking procedures. (If he even had a formal procedure.) So there’s nothing explicit for us to base our restocking techniques on. What we can do, however, is look at how a restocking procedure could be created to capitalize on the tools provided by the Arnesonian procedures we’re using.

Here are three approaches that I developed.

EMPTY ROOMS METHOD

The first option would be to simply rerun the original stocking procedure between sessions: Check each empty room to see if it now contains an encounter. If so, generate the encounter.

The problem with this method, even if it is limited only to the room that the PCs passed through during the previous session, is that it will, statistically speaking, usually lead to the generation of more creatures than the PCs are eliminating. The dungeon will slowly turn into an overcrowded tenement.

GLENDOWER TEMPLATE METHOD

An alternative would be to use your original dungeon key as a Glendower template during restocking: Check each empty room which has a protection point budget to see if it has been reinhabited. If it has, respend the original protection point budget and check to see if the room has treasure.

This method has the advantage of simplicity. It also eliminates bookkeeping during the session: You don’t need to keep track of exactly which areas the PCs have “tapped” in their explorations, you can simply check the key after the fact to see which areas have been depopulated.

A potential disadvantage of this method is that it can result in the dungeon becoming predictable: The same rooms will always be where monsters live, and the other rooms will never be filled.

Under the logic that your Glendower template was designed to present an interesting tactical challenge regardless of how its budget is “filled”, however, this might actually be viewed as a feature. Any predictability of the dungeon will also be undercut by your wandering monster checks. It’s not like there will be any place in the dungeon where the PCs will be “safe”; it’s more like there are certain areas of the dungeon which make for good lairs, and those are the areas that monsters keep moving back into.

QUADRANT CHECKS

When Arneson adapted the Blackmoor dungeons for convention play in the late ’70s, he instituted a quadrant-based system of wandering monsters: He divided the map for each dungeon level into a quadrant and pregenerated a random encounter for that quadrant. (“Players rolling a wandering monster in Quadrant A will have encountered Sir Fang!”) It’s an effective system for pushing specific, prepackaged content into play in a convention setting, but it’s not a system I was particularly interested in exploring.

For the purposes of restocking, though, this concept of “dungeon quadrants” interests me. It can be somewhat crude, but it also mirrors my own “sector” understanding of a dungeon complex. (These are the Tombs, this is Columned Row, these are the Worg training facilities, this set of rooms ‘belongs’ together, as does this one over here, etc.) If you wanted more detail, you could block out specific sectors. Quadrants, however, give you a simple one-size-fits-all approach that can be quickly slapped down onto any level of the dungeon.

You’ll still want to use common sense, of course: In the map above, for example, you can see how I’ve tweaked the borders of each quadrant on Level 1 to follow natural divisions in the dungeon corridors.

Here’s the procedure I’ll be experimenting with:

1. For each quadrant that the PCs entered during the previous session, there is a 1 in 6 chance that it will be restocked.
2. For each restocked quadrant, check each uninhabited room (using the normal stocking procedures) to see if it is now inhabited.
3. Check ALL rooms in the quadrant for treasure, although rooms that were currently inhabited only have a 1 in 20 chance of generating new treasure.

Note that this procedure can add new encounters even to areas that the PCs haven’t previously depleted. This is intentional, and a likely explanation would be creatures reinforcing their ranks in response to the armed thugs rampaging around their homes.

It’s quite possible that, after a little playtesting, you may want to tweak the odds listed here. As I write this, I haven’t actually had much chance to put these into practice yet. (I suspect 1 in 8 for the quadrant test might be a better fit. And the 1 in 20 chance for adding treasure to currently inhabited areas might be too low, but I’d rather be conservative with the money spigot.)

Next: Special Interest Experience

October 1st is Dave Arneson Day, a celebration of the Father of Roleplaying Games on the day of his birth. After writing up Reactions to OD&D: The Arnesonian Dungeon, I decided that I wanted to celebrate Dave Arneson Day this year by running Castle Blackmoor. And I specifically wanted to do so in a way which would closely emulate the feel of that very first session when Arneson’s players walked into the basement, discovered Castle Blackmoor, and ventured down the stairs into the dungeons beneath it.

I relatively quickly decided on a few mission parameters for this endeavor.

First, I wasn’t interested in trying to re-engineer the original rules Arneson used, if for no other reason than that this is, in fact, flatly impossible. Arneson kept no records of those rules, he never shared them with anyone (including the players), he redesigned them so often that I doubt even he remembered what the original rules were by 1973, and I’ve already done the “explore mysterious ur-text mechanics and cobble a game out of them” thing (see Reactions to OD&D).

Second, my specific point of interest was the way in which Arneson organically created the dungeon; i.e., the game structures he used for stocking and re-stocking the dungeon. As described in The Arnesonian Dungeon this is something that we’re able to tease out of the surviving record with a fair amount of detail (if not necessarily the specific charts and so forth).

Third, my interest in exploring the established canon of Blackmoor was fairly minimal. This can be a fascinating topic (although frustratingly scant; so many players, but very few memories, and the memories that have been recorded often contradict each other and the written records), but Blackmoor was (and arguably is) a living campaign with 40+ years of history which has been inconsistently reflected in disparate printed sources. Rather than enmeshing myself in that sort of Byzantine continuity, what I was interested in was creatively positioning myself in the same place Dave Arneson creatively positioned himself on Day 1 of the Blackmoor Dungeons and then moving forward from there.

What did this approach mean in practice?

• Take the original maps of the dungeon as presented in the First Fantasy Campaign.
• Recreate the original monster and treasure stocking tables to the best of our ability, then use them to stock the maps.
• Establish a minimal baseline of “established lore”, largely based on the material in the First Fantasy Campaign.
• Set up a scenario reminiscent of Greg Svenson’s recollection of The First Dungeon Adventure.
• Run the game using just the original three OD&D booklets.

I want to be quite clear here and reiterate that my goal is not to perfectly recreate Arneson’s original dungeon key. Or even to take the limited information we know about that dungeon key and then fill in the holes around those fragments. For example, the fact that I haven’t put 2 Lycanthropes in Area 18 of the 8th Level (as found in the FFC key) is not a mistake; that’s simply not what I’m trying to do here.

I was rather hoping to have all of this prepared for public presentation several weeks ago so that others could also use it for Dave Arneson Day this year. Unfortunately, I ended up going down a few too many rabbit holes with my research. (And, as I write this, I’m still trying to figure out to exactly what degree I want to rely strictly on the maps from the First Fantasy Campaign and to what degree I want to avail myself of other efforts to correct shortcomings and inaccuracies in those maps.) Hopefully you will still find it of interest, and perhaps some of you will find some other occasion for using this material.

If nothing else, there’s always next year, right?

STOCKING THE DUNGEON

STEP 1: CHECK FOR INHABITED ROOMS

• 1^st Level: 1 in 6
• 2^nd Level: 2 in 6
• 3^rd+ Level: 3 in 6

STEP 2: DETERMINE PROTECTION POINTS

• Roll 1d10 and multiply by the level’s protection factor.

STEP 3: ROLL ON MONSTER LEVEL TABLES

Simple Option: Once a creature type is determined, purchase the maximum number of creatures allowed by your protection point budget (minimum 1).

Complex Option: Roll Number Appearing on the OD&D monster tables. (This is indicated on the monster level tables for ease of reference.)

• Purchase as many monsters of that type as your protection point budget allows up to the Number Appearing generated (minimum 1).
• If you run out of Protection Points before hitting the Number Appearing and have points left over, purchase a weak version of the same creature (baby, etc.).
• If you purchase the full Number Appearing and have Protection Points left over, roll again on the monster level table to create a mixed encounter.

STEP 4: GENERATE TREASURE

Determine Presence of Treasure: 3 in 6 chance for occupied rooms; 1 in 6 chance in unoccupied rooms.

Determine Treasure Type

MONSTER LEVEL TABLES

Use:

• Group I for 1st and 2nd dungeon level
• Group II for 3rd and 4th dungeon level
• Group III for 5th+ dungeon level

GROUP I

GROUP II

GROUP III

* 2 in 6 chance the Balrog is guarding something (60% magical, 40% wealth).

Hobbit: Use kobold stats.

Giant Spider: Use Ogre stats, with a poison that deals full damage a second time on failed save.

DESIGN NOTES

Castle Blackmoor’s dungeons descend to Level 10 in the printed maps. (Reputedly only one expedition ever discovered the 11th Level, but the dungeons were said by Arneson to go as far down as the lava pits on the 25th level.) Despite this, the Protection Factor table ends at 7th Level because that’s as far as Arneson provided information. Beyond 7th level the value would have either capped or continued to increase. (But you run into additional problems in any case in the lack of Group IV monsters.)

I’ve used the OD&D # appearing entries here out of a sense of purity, although due to the “generate a tribe” mentality of those numbers they largely negate the point for the Group I creatures. You might consider ripping them out and replacing them with more dungeon-appropriate numbers (perhaps sourced from a later edition). The complex method utilizing the # Appearing entry is not strictly Arnesonian in any case. Use to taste..

Next: Special Monsters

RUNNING CASTLE BLACKMOOR
Part 2: Special Monsters
Part 3: Treasure Stocking
Part 4: Magic Swords
Part 5: Castle Background & Features
Part 6: The Dungeon Key
Part 7: Restocking the Dungeon
Part 8: Special Interest Experience
Part 9: Special Interests
Part 10: Blackmoor Village Map
Part 11: Blackmoor Player’s Reference

Reactions to OD&D: The Arnesonian Dungeon
Reactions to OD&D: Arneson’s Machines