Explore The Unknown With Operation Unfathomable
  • Explore The Unknown With Operation Unfathomable


    Are you looking for an old school adventure for your traditional fantasy games? Check out Operation Unfathomable, a dungeon delve for games like Swords & Wizardry that explores weird fantasy worlds. What will this adventure bring to your gaming table? Let's look and see.


    Operation Unfathomable is an OSR adventure by the Hydra Cooperative funded originally by Kickstarter. The PDF is 108 black and white pages and includes ten Swords & Wizardry pre-generated fighters and wizards (including a Neanderthal and a displaced jet pack dual pistol packing pulp hero). If you have ever wanted to start at 1st level with the chance to risk life and limb to acquire powerful magic items and quickly move up in levels, then this adventure is for you.

    A powerful band of adventurers led by a prince cut their way through an underground complex of monsters and magic. The PCs follow in their wake, intent on rescuing the prince (or at least the powerful magic item he took from his dad) and enjoying the reduced difficulty left behind because of all the slain monsters.

    The caverns hold many challenges. Chaos godlings spontaneously generate and begin wreaking havoc. There are twenty competing factions including opposed robot and giant bear-man from the future, Nul priests and their decapintante servants, sapient fungoids, underworld ranger patrols, blind antler men, worm priests, and more.

    Twelve strange phenomena range from blackout to whirlwind of unbidden transportation to stench of unknown origin. There are also twelve wandering horrors. Competing parties, strange phenomena, and wandering horrors all randomly occur as the party explores the caverns.

    The caverns themselves are well detailed as well with twenty-two areas of exploration. GMs combine these scripted encounter areas with the random events to combine the known and the unknown into an ongoing exploration of a living environment. If PCs fight a faction and wreck an encounter area that action will have consequences. The faction will warn their fellows to keep an eye out for troublemaking adventurers.

    An example of one area is the mini-dungeon detailing a local franchise Temple of Nul. The Nul cult can readily call for reinforcements with their long-range communication abilities and tend to react with violence. PCs who are captured by the priests of Nul may end up their prisoners.

    Nul believers experience a real sense of continual well-being by staring into a Nulís Abyss, but personal ambition becomes increasingly muted, relationships lose importance, and, ultimately, the individualís sense of self erodes away. Some believers become priests. The vast majority voluntarily commits ritual self-decapitation using cult relics (giant pruning shears), endure surgical implantation of a single steel antenna Chaos communication device extending from the stump, and serve as decapintante warriors in the Nul military.

    Even the temple is dynamic. There is a random chance that a small number of visitors will be at the temple. An alert will activate the decapitante warriors and summon the priests. The temple itself includes a Nulís Abyss, a surgical chamber, ape storage (two-headed giant ape mummy guards), treasury, and more locations for mayhem.

    Seven appendices expand on the history of chaos, the cult of Nul, hirelings, new rules (underworld ranger class, monsters, treasures, and spells), and pregenerated characters.

    Operation Unfathomable is both a mini-sandbox and a complete adventure. PCs could explore it for a few hours and be done or could spend months in the dark and strange caverns interacting with the weird, the dangerous, and the arcane.

    contributed by Charles Dunwoody
    Comments 5 Comments
    1. Polyhedral Columbia's Avatar
      Polyhedral Columbia -
      looks fun!
    1. Zhern's Avatar
      Zhern -
      Operation Unfathomable is excellent, but then again, pretty much everything from Hydra Cooperative is top notch. If you are looking for something out of the ordinary and reminiscent of a bad acid trip, then I highly recommend Slumbering Ursine Dunes, Misty Isles of the Eld, and Fever Dreaming Marlinko. Each of the aforementioned titles are for Labyrinth Lord but easily adapted to most any system.
    1. Charles Dunwoody -
      What I like about the adventure is you can run it as a short campaign concentrating on the adventure locations. Or you can expand it with the other random encounters to create a longer campaign several different factions fighting for control.
    1. warsign's Avatar
      warsign -
      never heard of this before, will try at once
    1. Jorge Jaramillo V's Avatar
      Jorge Jaramillo V -
      Quote Originally Posted by Zhern View Post
      Operation Unfathomable is excellent, but then again, pretty much everything from Hydra Cooperative is top notch. If you are looking for something out of the ordinary and reminiscent of a bad acid trip, then I highly recommend Slumbering Ursine Dunes, Misty Isles of the Eld, and Fever Dreaming Marlinko. Each of the aforementioned titles are for Labyrinth Lord but easily adapted to most any system.
      And Labyrinth Lord is better than Swords & Wizardry, anyway.
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