Castle Bravo: Trail of Cthulhu

Call of Cthulhu on Roll20

Call of Cthulhu


About the adventure

It’s March 1954. The Investigators are sailors and scientists deployed aboard the USS Bairoko to the South Pacific as part of Joint Task Force One to participate in a series of secret thermonuclear test shots in the Bikini atoll called Operation Castle. After the first detonation, the PCs will have more than just radiation to fear. This is a module designed for 4-6 players in the Trail of Cthulhu system. It involves Horror elements in a an atypical Cthulhu module set in the 1950s.

Professional Game Master

Alex L


13 Reviews

20 years as a TTRPG player

20 years as a Game Master

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Additional Details

How to prepare

Just bring yourself and make sure to have a Microphone and if you want a web camera.

What I provide

The adventure, the fun, and hopefully everything else required.

Gameplay details

Some warning about this module, much like many one shot Cthulhu games, it doesn't assume that everyone (or anyone) will survive the adventure, so be prepared for the possibility that your character will die horribly and probably at the hands of some sort of crazed monster.

Content warnings


Safety tools used


How will character creation work

Characters are pre-generated but you will have the ability to make modifications to personality, gender, or whatever modifications you feel are appropriate.

Players can expect

  • Combat/Tactics: Low
  • Roleplay: Medium
  • Puzzles: Medium
  • Experience Level: None

Player reviews (13)

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Castle Bravo: Trail of Cthulhu

13 Reviews

Price per player-session
You will be charged when a session starts


  • Duration: 4 to 6 hours
  • Number of players: 2 to 6 players
  • Experience required: None
  • Glowing demon knight leading an army of undead

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