Gygax’s Finches

The dungeon is a strange environment. And I don’t mean that just in the mythic underworld sense, but in the sense of Gygaxian naturalism. One of the basic issues is where do the monsters come from? For undead and demons and such the answer is basically “magic,” which settles the issue. Often these undead or demons or elementals or constructs were “stocked” by a necromancer or summoner who may or may not himself remain in the dungeon as the final boss lich. Similarly, we can imagine a mad wizard sending some lackeys to pick up an order for roper spores, stirge eggs, and a gelatinous cube starter culture at ye olde home and garden center. Of course the entire conceit of a mad wizard funhouse dungeon is don’t ask how it works, did I mention the wizard was insane, Bob’s your uncle. Let’s put such deliberately stocked dungeons aside and engage in the Gygaxian naturalism of thinking through how monsters might naturally occupy the ecological niche of the dungeon in the same way as we explain how the common raven came to occupy most of the northern hemisphere or the California mussel cling to every other salt-sprayed boulder from Alaska to Baja.

First, let us consider the simple case of monsters that are found in both dungeons and the wilderness. For instance, the orc is found on low-level dungeon tables and almost every wilderness random encounter table in OSE, Swords & Wizardry, and OSRIC. For a monster like orcs, it’s easy to explain how they got to a particular dungeon: they occupy lots of ecological niches and so even if two dungeons are separated by forest, or hills, or mountains, or first forest, then hills, then mountains; no problem, orcs inhabit all those places. Orcs are what biologists call generalists and it’s pretty easy to explain how generalists spread from place to place which is why some generalists (e.g., the common raven, the brown rat, people) have an enormous range. Generalist monsters like orcs that are found frequently above and below the surface might even form a single breeding population, but maybe not.

For instance, the orcs of the Misty Mountains at some point migrated from Mordor, crossing Rohan on the way. Or maybe vice versa, I don’t care enough about the canonical answer to read Encyclopedia of Arda, let alone the RotK appendices and the Silmarillion. The point is you can imagine orcs in Middle Earth having spread much the same way as human beings here on Earth. Human beings and zebras both evolved in an African grassland environment but we eventually reached the grasslands of South America and the zebras didn’t because we could also occupy the many diverse ecosystems between Kenya and Argentina. Once orcs are spread out enough over a wide enough range, you might get linguistic / ethnic / cultural differences among orcs in different areas, just as human beings show a lot of diversity, but how the orcs got there is not tricky.

The much harder problem is what about monsters that only live in the dungeon. The carrion crawler, gelatinous cube, rust monster, purple worm, cloaker, cave fisher, drow, duergar, and svirfneblin are all what biologists call specialists. One thing about specialists in real life is they tend to have limited range because even if there is another cozy dungeon a hundred miles away, you can’t get here from there. So a cave fisher in Temple of Elemental Evil might do very well by its offspring to lay its eggs in The Lost Caverns of Tsojcanth, but it is so hyper-evolved to live in a dungeon that it has no way to leave a dungeon in the Yatil Mountains, cross a few hundred miles of farms and forest, and settle in to another dungeon on the far side of Veluna.

There are a few solutions to this. One might be that maybe the monsters aren’t really limited to the dungeon ecosystem but go into other ecosystems. Drow settlers could travel overland by night seeking new dungeons to colonize. For more bestial monsters, they might spend some life stages in the dungeon and others out of it, with their non-dungeon life stage being harmless, which is why they don’t show up on the encounter tables. Harmless cloaker smolts could fly out of the dungeon and feed on insects only to return to the dungeon to reach sexual maturity and the phase of life where they have 6HD and feed on adventurers in preparation to spawn. But if you see a cloaker smolt the size of a handkerchief feeding on a grasshopper, you know the dungeon can’t be more than a few dozen miles away.

Mostly though the specialists will have a very limited range, perhaps even just a single dungeon. One dungeon might see the scavenger ecological niche filled by the gelatinous cube, but in another dungeon that job is performed by the carrion crawler. A more mechanically easy solution would be that several species might share a distant common ancestor but have diverged, at least in fluff if not in core mechanics. An example on earth would be ratites (long-legged flightless birds) which have been diverging for a very long time but an ostrich, an emu, and a cassowary still have a family resemblance to the extent that if you had to stat them out you could use the same stat blocks but might want to dry brush the minis a different color. In D&D, you can imagine lots of dungeons would have carrion crawlers, but they’d be superficially different in ways that might fascinate a sage specializing in entomology. And then there’d be the one weird dungeon where the carcass crawlers are the size of cats and have odd behavior, just as New Zealand has the kiwi, an unusually tiny and unusually nocturnal ratite.

This has a gaming implication in that once players get used to this Gygaxian naturalism conceit, if the players recognize that the monsters in this dungeon are the same breed as the last dungeon, they can infer that either the dungeons are connected or someone deliberately stocked one or both of the dungeons. “The carrion crawlers below the amphibian shrine have purple antennae and an iridescent pseudo-phallus, just like the ones roaming the mines of the abandoned dwarf city a few miles away, so at some point the two dungeons must connect.” An extreme version of this would be that any dungeon that has standard breeds of standard monsters is presumably somehow connected to The Underdark whereas anything that either lacks the standard dungeon specialist monsters or only has unusual breeds of them must be an isolated dungeon.

If you guys like this, next time I’ll do Gygaxian naturalism of sympatric speciation.

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  1. John

    You may have to be pretty heavy-handed with clueing in the players that these properties of monsters are actually meaningful beyond fluff (an easy clue to drop in their laps via a Sage), and then give them some big rewards for using the information while adventuring (e.g., a harmless-to-humanoids variant of a Carrion Crawler that rapidly outcompetes the murderous kind, and thus seeding a dungeon with the harmless version eliminates Carrion Crawlers as a threat after a few months?).

    If you did that though, my players at least would love it, and a sandbox game would add a dimension of identifying and classifying different species of dungeon monsters. Sounds awesome: I’m definitely going to try it.

    Liked by 1 person

  2. xaosseed

    I really like the theory of this – as mentioned in the other comment, I think one would need to clue in the players that they could get meaningful information by paying attention to these things but after that it would be tons of fun to slip out those details and let the players follow those breadcrumbs.

    Needless to say, keen to read the next installment!

    Liked by 1 person

  3. Taylor Lane

    Do you have a twitter or itch or DTRPG or something?


    1. gabrielrossman

      Flattering question, thank you. I don’t have a DTRPG account but will once I finish Satrap’s Army. Whenever I post, I post the link to the Sunday blog roundup on r/OSR. I have a Twitter account but it’s only infrequently about RPGs. Would you like me to create another Twitter account that is just an RSS for this blog?


  4. Taylor Lane

    Well, I actually already have an RSS reader. I use Feedly. It can’t seem to read your blog. I don’t really understand why. If you can fix that problem (what is going on there?) then I’ll just subscribe to your blog the normal way.

    My main reason for asking about your possible itch/DTRPG is that I wanted to read whatever you had written. My main reason for asking about your Twitter is because that’s how I talk to people in the TTRPG scene, and you seem like the sort of person I would enjoy talking to.


    1. GR

      Very nice of you, thank you. I’m @roguewpa. Please @ me to say hi if you follow.

      Will post here if and when I release something on DTRPG.


    2. GR
      1. Taylor Lane

        It does!


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