I love the Caverns of Thracia, a well known module in OSR circles written by the late Jennell Jaquays, and ran a solid 30 sessions centered around it a few years back. Over the years, I've seen a lot of confusion from folks trying to run Thracia, in particular due to the maps, and in my own case I had the most trouble trying to parse the nest that was Thracia's 2nd floor.
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This is the actual map for Thracia's second floor. |
It's a good map, but there's a lot going on and it's visually overwhelming at first, with rooms going above other rooms. Worse, there's multiple sets of secret doors and staircases that connect with several sublevels- though the room key considers them part of the second floor. Which makes it all a big horribly complex second floor blob.
My big lightbulb moment when running Thracia was that it isn't really one huge floor , at least from a GM point of view. While the players will absolutely experience it as a big mess of interconnected rooms, there are two separate levels here: the main set of caverns and fortresses held by the lizardmen and gnolls, and secret sublevels- the "public" areas that are actually inhabited, and then there is a set of secret chambers below those public areas, holding the mysteries of Thracia's ancient past, inhabited mostly by guardian constructs and undead. Very different vibes for a very different stratum.
All three of the submaps, as well as the little section of corridors in the middle of the main second floor map, all share this same vibe. And indeed, that little section of corridors ends up being the fulcrum section connecting the rest of the pieces of the map.
In other words, the way I think about Thracia, is that it has an extra floor- call it the true "3rd Floor", while the Minotaur's Palace are now the 4th and 5th floors.
Visualized like this:
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| Scale is not consistent, map is for comprehension. |
On the west side you've got the ancient serpent ruins, in the southeast corner you have the two floor room complex probably most memorable for the gemstone room, and in the northeastern section you have the Temple of Athena's basement. It isn't perfect, I probably could have figured out a way to show the two floor room complex better, but it is what it is. Hopefully it's clear enough, but it can't be worse than the original experience.
By visualizing the dungeon this way, you don't have to remember which submap links to where, you just have to remember the connections between the two floors- and the one place where the new "3rd floor" leads to the most secret level of Thracia, level 3A- conveniently, the numbering still works.
This makes the second floor map, when you clean it up, look something like this:
Personally, I think that small change, removing those central corridors that better belong with the "third floor", makes the second floor make way more sense. It instantly becomes clear what the pathing through the "public" areas of the dungeon is like.
I dunno if this will actually reach anyone who needs help understanding Thracia when they need help understanding Thracia, but hopefully it makes it easier to understand what the heck is actually going on in the dungeon. It's a great adventure, well worth powering through the difficulties for the modern DM.
