Gulf of Time

Agents are tasked with investigating an anomalous underwater reading picked up by early-warning hydrophones in the pacific. After an assembly, briefing, and a crash course in SCUBA diving (giving all agents the special training for SCUBA diving) at a field office at BAE Systems Shipyard in Hawaii the agents are given cover identifies as a documentary/research team and sent off aboard a small but capable research vessel called The Immaculate.

Their destination is the waters east of Samar Island in the Philippines. The trip will take a few days, agents can pass the time a number of ways:

  • Practicing SCUBA (gives +10 to a future SCUBA roll)
  • Research: pull some WWII Battle tidbits from “Background”
  • Study the anomalous readings: note any agent who does this. Despite the agents best efforts (and rolls) the readings are incomprehensible, and forcing the issue results in sanity loss 1/1d4.

The research vessel is simply a vessel to move the players to the adventure. Flesh out crew, details, etc as needed, but once the agents hit the water they’re on their own. Aboard ship, the agents can find basic SCUBA equipment and accessories such as lights, cameras, spearguns, metal detectors, etc. Don’t let a shopping trip or shore expedition derail getting to the wreck site.


In Leyte Gulf in October 1944 a small force of U.S. Escort Carriers, Destroyers, and Destroyer Escorts were engaged by a heavily armed Japanese force of Battleships and Cruisers. Primarily due to the better fire control of the American force, the small escort fleet punched well above its weight in it’s desperate struggle to get away from the battleships. However, during the Battle off Samar, the Destroyer Escort Samuel B. Roberts was lost.

A few hours into the tense battle, An 14-inch experimental Japanese hypergeometric heavy cruiser shell slammed into the Roberts, dooming her to the depths. Covered in sigils, equations, and signs the shell was designed to make up for the poor Japanese fire control systems by causing a temporal instability and stopping a ship in time. A frozen ship would be picked apart with ease. As a result of a miscalculation in the hypergeometric formula the shell didn’t freeze the ship, but instead trapped it in a loop of destruction.

The wreck of the Roberts is now sitting in 175’ of water is the source of the anomalous readings as the twisted wreck undergoes temporal instability.

The Wreck:

Once above the reading’s triangulated coordinates, the agents must dive down to investigate. Get a sense of what equipment the agents are bringing with them. The research vessel will remain on station but due to the vagaries of temporal disturbances it’s out of reach until the agents solve the problem. The agents can stumble right into the wreck or spend a few dives searching before finding the Roberts. It’s a twisted mass of metal rent and torn asunder under withering Japanese naval gunfire. It is a tomb for nearly a hundred sailors.

The Samuel B. Roberts is a Butler class Destroyer Escort. A diagram can be found here: and can be used as a general guide as the agents explore.

There are several points of access to the ship. On a luck roll any designed exterior hatch will work as long as two agents are straining to open it. Battle damage has opened up new routes of entry as well. As the aft 5” gun mount is gone, torn to pieces by an explosion in the breach, agents could swim down into the ammunition handling room. The aft engine room has a 40’ by 10’ hole on it’s port side, this is where the hypergeometric shell ended up.

Temporal Abnormalities:

As soon as the agents are aboard their mere presence alters the nature of the temporal abnormalities from a small, anomalous loop detectable only to highly tuned underwater hydrophones to a truly mind-bending experience. At first, agents notice barnacles disappearing, then battle damage should heal up around them. The goal is to trap and panic the agents. As their air runs out and things look desperate, describe what it feels like to drown, have them roll San 1/1d4 then describe them re-entering the ship as the temporal loop resets.

The next loop the agents should notice their depth readings decreasing as the ship unsinks and is lifted out from the deep with them inside. If they are too cautious to enter the ship, then they’ll see it lift off the bottom and glide upward. If agents note that they are ascending too fast, without decompression stops, knock off 1 san for noticing yet another thing acting as it shouldn’t. This loop is the last loop which plays out in reverse.

Once the agents are on the surface, either aboard ship or in the water, make sure they see the hypergeometric shell launch backwards from the hole in the engine room, screeching and causing visual and auditory disturbances as it sails back toward a nearby Japanese cruiser.

Forward in Time:

The temporal loop stabilizes somewhat, and until they solve the problem the agents are now repeating a 30-45 minute loop which ends with the ship getting struck and sinking. Start the loop wherever is appropriate and feel free to fudge it if you need a narrative or action to play out.

The agents are faced with several potential issues: Convincing the crew of the Roberts that these wetsuit clad invaders are friends, discovering the source of the temporal loop and stopping it, not getting caught up in the battle and getting injured, potentially trying to turn the tide of battle.

The agents are special, they’re outsiders which influenced the loop. Everytime the agents die the loop resets. If they are tempting fate by trying to survive more than the 30-45 minute window…well war is hell and there’s enough artillery flying around to take them out and cause a reset. They may also choose to reset themselves with a bullet to the head. This only costs sanity the first time 1/1d6. Agents retain their memories through the loops. Each loop should build, giving them a clue or a step towards a solution, then climax with destruction.

When the hypergeometric round strikes, it’s sigil-covered face sprays the interior of the engine room with formula and sigils like a paint grenade went off. Studying these can give the agents the upper hand in disarming the device later. Let agents roll any skill they think is useful, and give them bonuses for repeated studies over various loops. They’ve got about 10 minutes from the round striking to the ship sinking.

There are a few ways to solve the problem. They can simply alter the course of the Roberts (by force, or charisma) such that the round doesn’t strike. This solves the problem but strands them in the past unless they quickly don their SCUBA gear and dive after the sinking round. Since they know when and where the round will strike, they could also attempt to capture it. Fill the space with mattresses, or sling a net under the water and move the ship slightly, if it’s a clever idea it should work.

Disarming the round:

The round is covered in hypergeometric sigils and beneath the threaded piercing tip on the front is a dial with Japanese symbols. Unless the Agents know Japanese, this may be a guessing game. Studying the sigils on the ship may help them make an educated guess. It has 4 positions:

  1. Armed (this is where the dial is now)
  2. Safe (this disarms the round safely. This stops the loop, but traps the agents in the past)
  3. Reset (this returns the round to it’s point of origin, when the sigils were applied. In this case, to a secret factory floor somewhere in Japan. This stops the loops but gives the agents a whole new potential adventure).
  4. Clear (this disarms the round, and resets the time loops, dumping the agents back into their present at whatever location they are when they hit the switch)

If the agents are blind guessing, give them a 33% chance to hit Safe, Reset, or Clear. If the agents have studied the hypergeometric sigils but aren’t sure what is really going on, give them a 50% chance to hit Clear or Safe. If the agents have studied the sigils, understand what’s going on and have a clear goal then let them hit Clear.

Handler notes:

This scenario works best run on a quick time frame. Keep the agents moving forward, through loops, giving them clues or hints of clues each time. The battle is chaos, and there’s no time to get bogged down in planning or arguing over what strategy to take. When there is a lul, describe bits of the frenetic battle. If the agents have a clever idea, run with it. If the agents are stuck, perhaps an ally on the crew they’ve made has a good suggestion.


This was an entry to the 2019 Delta Green shotgun scenario contest, written by Kevin Ham.

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