Random RPG Thoughts #11: How MegaDungeon is D&D's Underdark?

Advanced Dungeons & Dragons was already waning for me when the Dungeoneers Survival Guide was published. We played several home brews by then, diverting more and more from 1E (first edition AD&D). A good friend bought the tome however, and we enede up flipping through the pages and thinking about its implications.
The rules were... a bit outdated for us already. We had moved to using skills earlier, based on RuneQuest. But to other players it was a sign that we probably were on the right track with skills, or that we could return to AD&D, because hey, now we had skills! Even if they were named "proficiencies". But there was something more intriguing about this book, except the bulk of rules and concepts we would never use.

A mega-mega Dungeon called Underdark
It was the idea of a huge underearth network. The Underdark. It was filled with whole peoples, cities, tribes, cultures, feuds, wars, wonder and treasure in a world wholly new. There lived Drow elves, mindflayers, and floating cities of Aboleth - whatever these were. It was a mega-mega-dungeon.

It wasn't mapped, we had to do that ourselves (some of us tried, cutting and pasting 3d geomorphs from photostats in the rear of the book). It wasn't layed out, or explained, we had to wait for years and several editions later before something more detailed came out. Sure it had been around as an implicit idea since 1978 in Vault of the Drow, but we never thought of it as a full setting. Now it glared at me and really sparked my imagination. A mega-mega-dungeon.

Now we didn't really have an idea what a mega-dungeon was at that time, in the mid-eighties. We couldn't fathom that it might be a real "thing" in a later movement called OSR. It just hit my fantasy cells, and I kept on thinking how cool it would be to run a mission down such a huge web of dungeons. As a player, that is. Because usually I was a Game Master, and still am.

Indiana Jones meets the Mosquito Coast
I figured I might play a Harrison Ford look alike, being a mix of Indiana Jones and the father in the Mosquito Coast - someone leading a mission (his family) so deep into unknown territory out of idealism, that he actually forgets who he has the ideals for, and ends up estranging his family instead. Even now, over twenty years later I wonder what it would have been if I could have played that character. Eventually I did play someone like it, named Alexander Mallory, but that was different.

We never did the deep earth exploring. Not even laying down a deep earth realm, much like Mordor, in our world Yaddrin, called Findath, did enough to really let it work. Bits and pieces, small forages, hit and run missions, one escape from its depths after a failed teleport. But no real attempt to hit into the heart of it. I guess we made the concept to scary and to unattractive to delve into.

Is it really a MegaDungeon, this Underdark, or What?
I'm not to sure if Underdark is a Mega-Dungeon. Giga-Dungeon is more appropriate, I guess. Probably people like Jovial Priest or James M. from Grognardia would know best. James is working on publishing his long awaited (judging from the pledges on his kickstarter!) Dwimmermount mega-dungeon, and that will probably be big - and unexpected and weird. Michael Curtis of Stonehell might know. What do you think? Does it qualify as the mother of all mega-dungeons? Or rather the mother of all giga-dungeons? Let me know.

Artwork thankfully borrowed from the Dungeoneer's Survival Guide: by Jeff Easley.


  1. Speaking as someone who has written my own megadungeon (Castle of the Mad Archmage), I think I might better characterize the underdark as a wilderness setting rather than a megadungeon.

    A megadungeon is somewhat more confined than the typical underdark setting. It has a more defined theme (whether or not that theme "makes sense", it's still present), and undergoes physical modification both in relation to the players' actions as well as the activities of the inhabitants. I'm not sure a traditional underdark setting would fulfill those criteria.

    1. Hmmmm. Intriguing distinction. Yes, I guess the Underdark is a bit more wilderniss-like, but still, it is confined - and underearth. And it probably would change by both player actions and what the races do.

      But if you say a (mega) dungeon would be more man-made (or creature / demi-human-made), with some sort of purpose behind it, then the underdark would not fit as a megadungeon per se.

      Parts of it might, such as an Aboleth city, or a Drow settlement.

      Any other opinions out there?

  2. Underdark = belowground wilderness, yup. That's how it's written in the DSG and that's how it normally runs in play. PCs travel for days with only a few encounters, usually miles apart, between actual adventure sites. So eg in my 4e game the PCs travelled for several days through the wilderness of the Underdark, having several encounters, to reach the Demon Queen's Enclave, a drow city/dungeon.