Swamp Rats, Chapter 1: Playtest Reflections & Lessons Learned

Welcome to the development log for Swamp Rats, a Pathfinder 2e adventure I’m developing for Foundry VTT. Here’s what I think after running Chapter 1 with two different groups. 

The first draft of Swamp Rats, Chapter 1  is complete, and I’ve taken two different groups through it so far. Both groups were composed of strong Pathfinder 2e players. One was my main crew — who are currently tearing through Abomination Vaults. The other was a team of seasoned players I recruited from the Pathfinder Discord. 

Lesson 1: Don’t Over-Polish Your Playtest Maps

I started with fairly polished maps, which I wouldn't recommend. It did give me a bit credibility since I'm new at designing adventures and nobody knew what they were getting into, though. I had to level up my map-making skills anyways, so it wasn’t a terrible move. Still, things change a lot from early drafts, so investing too much time in polishing maps early is a waste. Even a hand-drawn map would be fine if the players don’t mind a rougher visual experience.

Lesson 2: GM Often If You’re Designing Adventures

Running lots of games, both other published adventures and homebrews, gives you a solid baseline and helps you develop your own adventure design style. You quickly learn what works for you and what doesn’t.

For example, to challenge my Abomination Vaults crew, I need to stack encounters. After letting a ghoul escape, they ended up fighting nearly every ghoul on level 3 in one massive, session-spanning battle. I genuinely thought they were doomed — hoards of ghouls closing in (the cool pre-remaster ones with paralysis), clawing through barricaded doors, backed by their evil cleric leader. That edge-of-death feeling was SUPER memorable, especially since it was a consequence of earlier tactical mistakes. Since that was so much fun, I made sure these scenarios are a real possibility in Swamp Rats. I needed the GMing experience to know I wanted rolling encounters in Swamp Rats for the feel I'm going for.

Lesson 3: Really Use the Rules in Encounter Design

I really leaned into Pathfinder 2e's cover, stealth, and difficult terrain mechanics. They really fit the guerrilla warfare vibe I'm going for. From the player’s perspective, it should feel like XCOM or a Vietnam war movie: mistakes have harsh consequences, and your squad must learn to adapt quickly to the enemies and terrain to survive. Players were hiding in bushes, moving from cover to cover, exploiting and/ or avoiding mud and it was cool.

Lesson 4: Track Time & Resources for Real Tension

One lesson I learned from Old-School Essentials is that careful tracking of time and resources adds a ton of tension and engagement. I don’t hand-wave this — players know the consequences of taking time. I roll for random encounters every 10 minutes in the dungeon, and events progress on a timeline in the world at large. 

This keeps players alert, especially during those 10-minute intervals spent healing or meditating. My second group nearly TPKed after barely fending off some frogmen, then just assuming they could spend time healing up without securing the area. The frogmen returned with reinforcements. As soon as the frogmen kicked in the door, one player said, “Fair.” Also, hearing, “We’re dead,” followed by a miraculous comeback was awesome.

Goal-based XP

I don't necessarily love giving XP for killing monsters or getting treasure because it incentivizes those behaviors. I prefer giving out XP for accomplishing a goal. This works very well for military-style, mission-based adventures.

Both groups accomplished all three "missions" and spent about 12 real-life hours at level one. I was worried it might be too long, but it felt about right. Level one is the sketchiest level, and they definitely all earned their second level.

Not for Beginners—And That’s Okay

Swamp Rats, Chapter 1 throws multiple extreme-level encounters at 1st-level characters, expecting them to use clever tactics to survive. Both groups made it though, but both had at least one near-TPK.

This adventure is probably too tough for beginners. That’s fine. A real possibility of death is essential for guerrilla/ horror adventures. It needs to be scary to work. Like Dark Souls, it’s not for everyone, but the sense of accomplishment is greater for those who survive. Real adventures don’t guarantee success.

Lesson 5: Playtesting Is Key

Playtesting is crucial for adjusting encounter flow. For example, I wanted a swamp fight to feel like a tough slog, but the map was too big and players were spending entire turns just moving, so I condensed it to make it slightly less grueling.

From the playtest, I also realized that I needed a whole other wilderness map and a random encounter table for patrols, after both groups decided to spend more time coming back to HQ than I thought they would. I’m also adding items and stats for breakable stuff in response to clever player ideas that emerged during play. Good GMs improvise, but it’ll be helpful to have those details baked in.

A Little Gonzo is Good

The goofy moments were OK—they offered (dark) comic relief and fit the somewhat gonzo sci-fi setting. I love how Neal Stephenson’s Snow Crash balances gonzo elements with serious modern-day themes. Post-apocalyptic games like Fallout and Wasteland do this so well that it's become part of the post-apocalyptic genre. I also love the trope of having settlements that are caricatures of modern day political factions, that players are free to ally with or go against. Similar factions were hinted at in Chapter 1, and will come to the forefront more once the campaign opens up more in later chapters. They worked well so far.

Now to Polish and Publish

Overall, I’m happy with where things are. I can see the final form clearly, and I think it’ll be a decent first product. The heavy lifting is mostly all done (except for the illustration — woah, that’s a huge challenge and so important; more on that in another post). Now it’s all about production and polish. The learning curve for this first project was steep — taking illustration classes, learning new map-making tools, getting better with Foundry VTT, and so much more. But it was also a blast, and I plan on doing a lot more of this!