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Operation Unfathomable
BEHOLD the Underworld in all its bewildering majesty as titanic Chaos Godlings and their unsavory cults make genocidal war upon each other!
SEIZE eldritch artifacts and treasures far above your lowly station!
THRILL as you throw the gauntlet of your life into the smug face of the unknowable and embark upon OPERATION UNFATHOMABLE!
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OPERATION UNFATHOMABLE is a 108-page, internally-consistent, gonzo funhouse module for Swords & Wizardry that runs like a subterranean wilderness trek instead of a “down the 10 foot hall and kick in a door” affair. There are random elements aplenty to keep GMs guessing as well as players. No balanced encounters to be found here, but the clever setup allows low level characters to drop into the dungeon “deep end” and still have a chance of making it out alive—if they’re smart and wary.
OPERATION UNFATHOMABLE includes:
- Underworld Phenomena: Novel environmental hazards to challenge explorers like Horizontal Cave Lightning, Whirlwinds of Unbidden Transportation, Sudden Seismic Events, and many more!
- Fractious Factions: Enter a crossroads of Underworld civilization where combat is only one of the options (and often not always the wisest!) for dealing with its denizens. The PCs can make a temporary truce with Blind Antler Men or forge an unlikely alliance with the minions of Nul the Mindless God!
- Races, Weirdos and Chaos Godlings Galore: Over two dozen new creatures, from Batwinged Dwarfs to Shaggath Ka the Worm Sultan, malevolent...and even more malevolent!
- Near-Endless Adventure: Enough NPCs, encounters, and areas to explore to keep a campaign going well beyond the initial scenario.
SEIZE eldritch artifacts and treasures far above your lowly station!
THRILL as you throw the gauntlet of your life into the smug face of the unknowable and embark upon OPERATION UNFATHOMABLE!
---
OPERATION UNFATHOMABLE is a 108-page, internally-consistent, gonzo funhouse module for Swords & Wizardry that runs like a subterranean wilderness trek instead of a “down the 10 foot hall and kick in a door” affair. There are random elements aplenty to keep GMs guessing as well as players. No balanced encounters to be found here, but the clever setup allows low level characters to drop into the dungeon “deep end” and still have a chance of making it out alive—if they’re smart and wary.
OPERATION UNFATHOMABLE includes:
- Underworld Phenomena: Novel environmental hazards to challenge explorers like Horizontal Cave Lightning, Whirlwinds of Unbidden Transportation, Sudden Seismic Events, and many more!
- Fractious Factions: Enter a crossroads of Underworld civilization where combat is only one of the options (and often not always the wisest!) for dealing with its denizens. The PCs can make a temporary truce with Blind Antler Men or forge an unlikely alliance with the minions of Nul the Mindless God!
- Races, Weirdos and Chaos Godlings Galore: Over two dozen new creatures, from Batwinged Dwarfs to Shaggath Ka the Worm Sultan, malevolent...and even more malevolent!
- Near-Endless Adventure: Enough NPCs, encounters, and areas to explore to keep a campaign going well beyond the initial scenario.
- GenresRole Playing Games
108 pages, Paperback
Published February 5, 2018
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November 20, 2025How? I bought a Bundle of Holding, I think, but then I found a copy at the Half-Price Books, and I wanted to check another big dungeon (after Stonehell).
What? This review is going to cover (briefly! (I hope))
- Operation Unfathomable, the original dungeon delve
- Odious Uplands, the expansion about the wilderness above the dungeon
- The Dungeon Dozen, vol 1-2, a collection of mostly d12 random tables
In Operation Unfathomable, you get asked to go into the underdark to retrieve the emperor's child or more importantly, an artifact he took. That artifact was a Nul wand, which is wanted/involved in several factions:
- There's the worm/chaos godling that was wounded
- There's the Nul priests and followers (who cut their heads off and replace them with antennae)
- There's the fungus people who are interested in science
And there's a few other factions and groups (there's a time traveling robot who wants to end magic and the bear professor who wants to stop him, there's a slugman merchant, and a lot of wizards with bodyguards), but I don't want to get into them because I want to step back and note the similarities: there's a lot of things that could kill you, but there's also a pervasive weird science thing going on, with a lot of characters interested in researching something or other. (One of the pregenerated characters you can play has a ray-gun, and there's more where that came from.)
The Odious Uplands is a sandbox, and while there's less science-y stuff, there is sort of a strange science thing going on, in that these odious uplands are populated by neanderthals and evolving apes: it's like a gonzo science-fantasy version of an ice age. (Perhaps that's the time-traveling element again.)
So, taking a step back, I feel like I could point to general areas of interest for Sholtis: time, fungus, ray-gun sf. (Also, he doesn't do all the art, but he does some, and as art director for this book, I feel like I can also say: aesthetically, he likes stretched out guys. Very few squat people, and even the giants seems like taffy pulled almost too far.)
Both these books have a lot of random tables, and many of them seem fine and useful (like, "we search the fungal bloom, what do we find?"); and that is continued in Sholtis's books of random tables, and yet, kind of like the dungeon/wilderness, I almost feel there's too much stuff going on. There's some interesting and fun tables (like different tables for the different classes about what you did before you started adventuring) and fun entries (like the vampire lord's potential guest list includes a vampire whale), and yet, it's hard to see how some of this stuff wouldn't immediately become the center of the campaign if you put it in.
Yeah, so? I enjoyed this book and I might return to it at some point (though the science-fantasy angle sort of misses me) but I don't feel the need to own it in paper just to flip through.
What? This review is going to cover (briefly! (I hope))
- Operation Unfathomable, the original dungeon delve
- Odious Uplands, the expansion about the wilderness above the dungeon
- The Dungeon Dozen, vol 1-2, a collection of mostly d12 random tables
In Operation Unfathomable, you get asked to go into the underdark to retrieve the emperor's child or more importantly, an artifact he took. That artifact was a Nul wand, which is wanted/involved in several factions:
- There's the worm/chaos godling that was wounded
- There's the Nul priests and followers (who cut their heads off and replace them with antennae)
- There's the fungus people who are interested in science
And there's a few other factions and groups (there's a time traveling robot who wants to end magic and the bear professor who wants to stop him, there's a slugman merchant, and a lot of wizards with bodyguards), but I don't want to get into them because I want to step back and note the similarities: there's a lot of things that could kill you, but there's also a pervasive weird science thing going on, with a lot of characters interested in researching something or other. (One of the pregenerated characters you can play has a ray-gun, and there's more where that came from.)
The Odious Uplands is a sandbox, and while there's less science-y stuff, there is sort of a strange science thing going on, in that these odious uplands are populated by neanderthals and evolving apes: it's like a gonzo science-fantasy version of an ice age. (Perhaps that's the time-traveling element again.)
So, taking a step back, I feel like I could point to general areas of interest for Sholtis: time, fungus, ray-gun sf. (Also, he doesn't do all the art, but he does some, and as art director for this book, I feel like I can also say: aesthetically, he likes stretched out guys. Very few squat people, and even the giants seems like taffy pulled almost too far.)
Both these books have a lot of random tables, and many of them seem fine and useful (like, "we search the fungal bloom, what do we find?"); and that is continued in Sholtis's books of random tables, and yet, kind of like the dungeon/wilderness, I almost feel there's too much stuff going on. There's some interesting and fun tables (like different tables for the different classes about what you did before you started adventuring) and fun entries (like the vampire lord's potential guest list includes a vampire whale), and yet, it's hard to see how some of this stuff wouldn't immediately become the center of the campaign if you put it in.
Yeah, so? I enjoyed this book and I might return to it at some point (though the science-fantasy angle sort of misses me) but I don't feel the need to own it in paper just to flip through.
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