NOTE: Spoiler warning appears further down—this section is safe for players.
“CAS-1: The Trouble in Twin Lakes” is…
- A mystery/investigation module with horror themes
- Set in a rural area near a dark forest
- Adventure #1 in the “Cairn Adventure Series” [CAS-1] for Cairn 2e
- By Yochai Gal, creator of Cairn
- Free to download!
While Yochai states that its’ “suitable for both new and veteran players,” I certainly don’t think it would feel vanilla or boring to seasoned players. In fact, I enjoyed reading it so much I’m considering running it myself.
Ironically, I read this during a short bout of illness. This module legitimately gave me fever dreams—terrifying ones! That’s a solid compliment for a game that leans into horror.
Usability – 3.5/4
Like most good OSR adventures, Twin Lakes is written with usability in mind. I really appreciate the page 1 section, “What’s Really Going On Here?” and the Important NPCs summary (pages 4–5) is a big help.
As a Game Master, expect more complexity than in your average OSR one-pager. This is a 24-page adventure with a real mystery at its core.
Yochai (and Brad Kerr) often praise “read once and run it” modules on their podcast, Between Two Cairns. I don’t think CAS-1 quite fits that description—not due to poor writing, but because of the mystery’s complexity (which is a good thing). That’s why I’m giving usability a 3.5/4. Still, the format and style are engaging and clear. Just be ready to read it once—and maybe once again for notes.
GMs should also check out Yochai’s Cairn 2e Warden’s Guide (also free) for background on the setting. Otherwise, you can drop this adventure a few days’ travel from any major city. It could easily be adapted to most old-school RPGs with minimal work.
Art – 3.5/4
The art is great—ranging from gorgeous to genre-appropriate. The cover sets the tone perfectly. All maps are detailed and suited for GMs, with a style that fits the OSR zine vibe.
The dungeon map itself is excellent, though not ideal for dropping directly into a VTT (since certain items would need to be hidden). For a group like mine that uses VTTs, this slows things down a bit. That’s the only reason for the slight markdown here.
Special shoutout to the art on page 20—one of the most evocative pieces I’ve seen in an RPG in a while. I’ve stared at it longer than I’d like to admit. It’s so good, it deserves a T-shirt, a playmat, or a poster. I wish I knew who the artist was—can’t find a credit anywhere! [EDIT: Yochai posted below with this clarification: “The artist is Wuggy (Ari-Matti Toivonen). All of the art is by him, except for some of the interior maps (those were done by Adam Hensley).” Thanks, Yochai!]
Story – 3.5/4
[Spoiler warning for players—stop here!]
I really, really like this story.
(I’m just procrastinating some blank space for players to bail)
When I first got this adventure, I was skeptical about Yochai’s note that “[w]hat appears at first to be a set of interconnected events are…completely unrelated.” Two disappearances in the same town that are just coincidences? That almost made me shelve it. But I think most players won’t notice (or mind) this detail, if they read past that page.
In truth, the disappearances aren’t completely unrelated. The reeve of Isthmus Town and his lackey are tied up in everything. They might not be behind all the events, but they’re the connective tissue. Even though I’m spoiler-warned here, I’ll avoid blowing the whole plot. Trust me, there’s enough crimes connecting back to this guy to put him away for a loooong time. That could easily set your adventurers up for some fun future adventuring.
The dungeon is a masterclass in simple, thematic design—but don’t expect it to be easy. Depending on how long the players investigate, there’s a real chance the boss could wipe the party. Still, it’s a fantastic dungeon, and highly recommended.
I’m seriously considering running this for Cairn. I estimate it could last 3–4 sessions. If you like Cairn or mystery adventures, definitely check it out!
Leave a Reply