Thursday, December 29, 2011

Megadungeon Mapping

Do we need to limit ourselves to a large map?

I know it's a strange question in regard to megadungeon design but, do we really need a big map for each level of a megadungeon or would it perhaps be easier to map a wider variety of connections and arrangements by having a bunch of smaller maps focusing on small sections of the megadungeon instead of one overall map?

Here are six map sections illustrating the princiople:

The arrangement of these maps isn't set yet which shows an advantage of this method of design. A suite of rooms can be moved to where it's more useful after it's designed. The section can be relocated as the dungeon is being designed and could also be moved to another section of the dungeon for reuse geomorph style or the map and all details can be moved to where the players exploring the dungeon will find it.

The connections and distance between these sub-maps is all up to the DM of course. Even if section 1 and 2 connect off the north corridor for me and you there could be another DM that while they like section 2 would rather not have it sitting connected to section 1. A small changes in notes and it's moved, no(or little) redrawing required. Less material can be used to cover more area.

Another advantage to this scheme is in stocking and re-stocking. The small sections can be worked up in digestible bites. A half dozen or so rooms can be written up and tied to each other without the stress and intimidation of trying to connect the other 100 or more attached areas on the same level.

This design also makes adding to the megadungeon easier on the DM just add a new section where you wish without having to re edit maps. Section 1 and 2 can still connect to each other but if you've had a great idea that would work out dropped between sections 1 and 2 you can add it without screwing up your overall map. This seems to be a great way to have the ever growing and expanding megadungeon without having to re-dawmaps over and over again.

Lastly this method totally defeats the "let's search the whole sheet of paper" style of dungeon exploration.

What do you gentle readers think?


  1. This is one of my favorite mapping concepts. A very similar idea is Geomorphs, which are little square map pieces with semi-standard exit points on the sides so they can be used together for random map generation.

    Check out and

  2. @citdoors, thanks comment and for the links, I'm hip to the geomorphs-

  3. I think this is good stuff. I might try this for my next dungeon level, maybe use a single geomorph for each subsection.

  4. I've always had the intention of building out a megadungeon like this: I have a larger-scale map at the scale of 100-200 feet per square. I divide that out into blocks and label them with evocative names like "Drowned Crypt" or "Shrines of the Mountain Cults". Then I take the appropriate measure of the blocks and map it in whatever scale I need to for the submaps.

    I wish I had an example to show you, but my road to Hell is paved with those aforementioned (good) intentions. Maybe I can describe it... like, say on the large map, at 100 feet per square I do a 2x3 area called "Cave of Snares." That gives me the general theme of that area (and a nice name that can be part of rumors about the place, etc), and when I map it in detail for play I can just do a 10 feet square map of that area, twenty squares by thirty squares. Done and done. You just have to make sure your entrances and exits all line up properly.

    Now, if you are mapping your megadungeon the way Al of Beyond the Black Gate does here, then this method may be useful, or my envisioned method may be useful. It depends on if you are building one contiguous dungeon and want to chop it up into themed sections that are akin to one-page dungeons, or if the whole thing is connected with large, sparsely-distributed corridors that crop into small areas with chambers.

    If you are building an underground wilderness or some sort of swiss-cheese underdark with ruins and carved out shrines, "Saturday Night Specials," etc., like I always pictured the Underworld in EPT to be, then yours may be even better; you just do a map with tunnels as lines and nodes on the graph that correspond to your miniature maps that are ruins, temples, caches, Saturday Night Specials, etc.

    Hmmm, now you have me thinking...

    That said... is BigDungeon dead?

  5. @restless, as to the aforementioned good intentions...BigDungeon isn't dead but it is certainly due for a reboot. Part of wrestling with that inspired this post. I've got a game related project to finish and a new house to finish moving the family into but BigDungeon will get a reboot in 2012.

  6. This kind of "map the connections, and then only detail-map the important encounters" idea has deep roots. That's how D1-2 was organized, and it's essentially pulling the wilderness adventures approach into the dungeon. It works.

  7. An interesting idea, but in actual campaign play it's quickly going to lock down: Once the players explore an area, they're going to expect it to have the same floorplan the next time they come through unless there's a really good reason why it isn't.

    This may save you some prep time (since you can simply lay whatever new stuff you've got in front of the players no matter which direction they explore), but you do so at the cost of railroading your players.

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  9. Take a piece of graph paper. Draw a box hemming in 26x26 squares. Write 1-26 across the left side, one number in each square along the outside. Write A-Z along the top similarly. Above this write LEVEL ONE. This is your Level Map.

    On the next sheet of graph paper, draw a box hemming in 30x30 squares. Above, write LEVEL ONE M-13. Each square in this Local Map is 10' across. That means each Local Map is 300' x 300'. This square Local Map corresponds exactly to square M-13 on your Level Map. That is, on your Level Map, find the M row and run your finger across to the 13th column. That is your M-13 Local Square.

    26 Local Maps x 300' per Local Map equals 7,800' x 7,800' per dungeon level, or about 2.1 sqare miles.

    You can develop your Local Maps as you need to. Just make sure they line up. For your sanity, on each edge where there is an exit, label the Local Map that you'll get to if you go through the exit. So if you see a set of stairs down, from 1-M-13, write 2-M-13 on it if it goes down to the next level. Write 5-M-13 if it goes down several levels.

    On your Level Map, for Level One, draw a dash across any connections. So if M-13 connects to the Local Map to the north and to the east, draw a vertical line across the north border of M-13 and a horizontal line across the righthand border of M-13. If there's a connection upward, draw an up-arrow in the box, and if there's a connection downward draw a down-arrow in the box. It doesn't matter if you have multiple connections, just one arrow will suffice. If you have connections that go up AND down in the same Local Map, do the up-down arrow instead. Ths is useful for looking at the Level Map to find ways through the dungeon on a larger scale, and for answering questions like "I use Find the Path for stairs down" or something.

    You can draw in with colored pencil to describe the territory of various intelligent creatures that may cover multiple Local Maps.

    The Local Maps are put in a binder in clear sheet protectors, arranged so when the book is open, the left sheet is the map and the right sheet is the map key. So every sheet protector has a map key for the previous map and also a map, on opposite page sides.

    So you have the template for a dungeon that would otherwise span over 16' x 16' per level. And as always your level depth can be as much as you want, and you can have sublevels of however many Local Maps you like.

    Which brings me to the point of this: I've found that a 30x30 One Page Dungeon template for each level works just fine. You can fit a whole lot in there, even a whole village or a district of a town. I find that it's fun to work within constraints like that, where you have to figure out whether that room really needs to be 40x40 or if it can get away with just being 20x20. You arrange hallways more economically. You start to realize that an Orcish kitchen can really be just a 20x20 room and the larder can be hung in the ceiling and under tables instead of being a separate room.