Convergence: Reviewing and Improving the best scenario ever

Ok, maybe not the best ever, but close. In this post I will discuss one of my favourite rpg scenarios for any system, Convergence, by John Tynes. It was first written for Call of Cthulhu and is now available for Delta Green.

As usual in my reviews, I will start with a short bullet list summary intended to give a general opinion of the scenario without any spoilers. I will then go in depth (with spoilers) and add some suggestions to improve the scenario (yes, I am arrogant enough presume I can improve upon what I consider one of the best scenarios ever). 

TL;DR:

Positives:

• How can I make it more positive than saying it is really one of the best horror scenarios ever?
• Slowly creeping paranoia that turns into extreme paranoia
• Immersive body horror 
• One of the scariest set pieces I’ve ever had the pleasure to GM in an RPG

Negatives:

• Very unforgiving: likelihood of a TPK is only reduced by GM “niceness”
• The need to constantly escalate leads to a couple of over-the-top scenes
• Lacks material to help the Keeper/Handler/GM bring it to life; too much information needs to be inferred or made up during the session. Before the 2023 edition, it didn’t even include a map of Groversville, leaving you to figure out the layout on your own.
• The plot has some small inconsistencies.

Overall:

• One of the greatest horror scenarios ever written
• ...but it could offer more tools to help the Keeper/Handler/GM run it smoothly.

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Delta Green:

I’m a big fan of Delta Green. Before it became its own game, Delta Green was a sourcebook for Call of Cthulhu, allowing players to take on the role of U.S. government Agents working in secret to protect the population from the horrors of the Mythos while keeping them blissfully unaware of the terrifying things lurking in the dark.

As far as I know, Delta Green began with one scenario, the eerie Convergence, published in The Unspeakable Oath #7 in 1993, which remains one of the scariest Call of Cthulhu/Delta Green scenarios ever written.

Following this, we got the Delta Green sourcebook, which introduced players to the conspiracy’s Agents and their enemies, including Mythos-aligned groups like the neo-Nazi Karotechia and the U.S. government’s Majestic-12. The sourcebook also included a revised version of Convergence. Published in 1999, it captures the same conspiracy-laden atmosphere as The X-Files—even though Convergence predates the show—with shared themes like UFOs, government cover-ups, and secret experiments on unwitting civilians. However, Delta Green is darker, more pessimistic, and, of course, Lovecraftian.

Convergence: what is it about?

Convergence is set in the small town of Groversville, where strange events have been occurring. The Agents (player characters) are sent to investigate after a local boy kills his father and embarks on a cross-country rampage, robbing gas stations for comics, candy, and painkillers, while occasionally murdering people with superhuman strength and resilience. Upon discovering that the boy’s muscles were replaced with hyper-dense biological tissue (in the scenario is called “proto-matter”), the Agents travel to Groversville—a town of around 1,000 residents now infamous for UFO activity.

From the moment they arrive, the town feels off. Many residents report “losing time”—disappearing and reappearing with no memory of the in-between. While the townsfolk are generally friendly, the Agents constantly feel like they’re being watched.

Then, things escalate. One of the Agents loses time and soon realises their digestive system is behaving strangely. This is immensely creepy.

Then, investigating a room in the motel where they are staying leads to one of the most terrifying set pieces I’ve ever run in an RPG: they discover the corpse of a man in a bathtub filled with bloody water, with white goo sprouting from his head. As the Agents investigate, something stirs in the water—a small, crawling, amorphous creature, gooey and monstrous. During the battle with the creature, the goo on the corpse vanishes, and the Agents find themselves facing yet another monster. This scene always shocks the players, often ending with a character or two dead, and usually leads to drastic measures, like burning down the motel to ensure none of the goo creatures survive.

In another room, the Agents find a young girl pregnant with something inhuman— a result of the same proto-matter that mutated the boy, created the goo monsters, and infected one of the Agents.

To make matters worse (and this is another masterstroke from Tynes), the Agents receive a spray from Delta Green that detects proto-matter by making things glow pink when sprayed. When they test the town’s water supply—the same water they’ve been drinking—it tests positive. In fact, if the Agents have drunk any tap water since arriving in town, they are now also infected with proto-matter.

The horrible truth is that the Mi-Go are using Groversville as an experimental site, starting with cattle and moving on to humans. Different versions of proto-matter are used in these experiments, including one that infects the water supply, allowing the Mi-Go to see through the eyes of infected individuals and control them—potentially turning the friendly townspeople into psychotic killers intent on eliminating the Agents. Worse, the Mi-Go can even control the Agents themselves if they’ve been in town long enough.

The Agents' only hope is to discover the Mi-Go’s base of operations, located in a barn atop a hill. However, getting there is no small task—the Mi-Go can easily track the Agents through the infected townspeople, and if the aliens detect them, they’ll trigger a kill switch that transforms the proto-matter into a deadly virus, wiping out anyone infected (including the Agents). To succeed, the Agents must locate the barn, infiltrate it undetected, and destroy all the Mi-Go before the aliens activate the kill switch.

Without a particularly generous Handler (GM), this scenario is almost a guaranteed TPK. For this reason, I often refer to Convergence as the "Kobayashi Maru" scenario.

There is no beauty without a flaw

So, is this a perfect horror scenario? It comes very close, though there are a few missed opportunities and gaps in the written material that require the Handler to improvise in areas that should have been fleshed out. This has improved somewhat with the new 2023 edition—we finally get a map of Groversville, for instance—but there’s still a lot missing.

I used to run the scenario based on the old Delta Green sourcebook version, where little information was provided about the people living in Groversville. With no map included, it was up to the gamemaster to create all the locations, NPCs, and personalities, ensuring they aligned with the handouts—particularly with the long handout found with the dead reporter in the motel. This handout describes his investigation into mutilated cattle, people losing time, and sightings of helicopters and strange lights. If the Agents decided to investigate these occurrences, there was virtually no information in the scenario to flesh out these elements. Even in the 2023 version, although we now have a map of Groversville, there is still only a note regarding the handout, saying that it is up to the Handler to figure out how the Agents can obtain the same material by interviewing the locals. I’ve mentioned before that I don’t particularly enjoy scenarios overloaded with information I could create myself, but this feels rather extreme, as you have to create about a dozen NPCs and provide them with testimonies that fit the narrative.

Another issue with Convergence is that, at times, it feels like a horror "greatest hits." For instance, not only do we have the Mi-Go hiding in the barn, but they also use Grey dolls to make people believe they are Greys rather than Mi-Go. Additionally, there’s a bizarre proto-matter abomination in the city hall, created by merging all the members of the town council (though explaining why the Mi-Go would do this is a bit tricky). Moreover, Majestic-12 is monitoring the situation with helicopters, and a sensationalist TV crew is running around. Some of these elements make the plot feel contrived, or at the very least complex, so I often omit them (I tend to remove the TV crew, which becomes a distraction, and downplay the city hall situation, which can lead to a confrontation that the players assume is final—but isn’t. In fact, if they attack the monstrosity in the city hall, they likely lose the scenario because it triggers the Mi-Go to release the virus).

How to prepare Convergence

I’ve run Convergence many times, and one thing I consistently do is create a cast of interesting NPCs for the Agents to interview, where I try to insert a bit of Twin Peaks-style weirdness. I want the players to feel like something is off, but just subtly—missing memories, detached behavior, slight physical abnormalities—enough to make them suspicious, but not enough to drive them over the edge. In particular, I developed the character of the pregnant girl’s mother, who is in a more advanced stage of proto-matter replacement than the Agent with a similar condition. This creates a very unsettling scene when the Agents interview her: she walks around the house, extremely obese and seemingly unaware of her state, while all the recent photos of her show a fit, middle-aged woman.

I think it’s important to make the sheriff a tough but friendly, helpful man who doesn’t like having federal agents around (in my version, he doesn’t trust the federal government), but treats them fairly. Make the players like him. Because when, controlled by proto-matter, he turns into a mindless killer, the impact is much stronger.

And my own masterstroke

The biggest change I made to the scenario is one that has been praised by players time and again. In the original scenario, the Agents are called after the boy with superhuman strength is captured at a gas station. They see him on a surveillance recording, where he kills a man with a decapitating uppercut, and then they’re taken to the jail where the boy is being held.

I felt this scene was a missed opportunity for a more dramatic, in-media-res opening. So, I created a new intro for the scenario.

The Agents are urgently sent to a gas station to investigate. There’s no time for a briefing, and as they drive, the Delta Green handler informs them over the phone that three gas stations have been attacked with extreme violence over two days, along a straight line from Tennessee to Georgia. The Agents are headed to a gas station on the same road, suspected to be the next target. Delta Green doesn’t know exactly what’s happening yet, as it’s taking time to retrieve the surveillance tapes from the other locations (this being the 90s).

As the Agents approach the gas station, they realize it looks like a riot has taken place. They see broken windows and shattered cars, and they pass the mangled body of a police officer lying near the gas pumps. Inside, they find more bodies, blood, and a desperate, crying teenager. As they attempt to calm him (or threaten him), he suddenly flies into a rage and attacks them violently. This intro often results in the death of one agent. Typically, the Agents end up riddling the boy with bullets and, following their handler’s instructions, load his body into the trunk for inspection. After about 20 minutes, the "corpse" begins banging on the trunk from the inside, forcing them to shoot him again (and lose some sanity).

Players often tell me this intro is the creepiest scene in the entire scenario, which makes me extremely proud since it’s my own addition to what I already consider one of the most terrifying scenarios ever written. 😊

I’ve thought about expanding this intro into a standalone one-hour scenario, but it works so well as the opening to Convergence...

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