Beyond a grippli village sits an abandoned temple forgotten to time. But an evil emerges that has not forgotten the temple and is willing to make any sacrifice to find its secrets.

Book of Cylinders is an adventure for 6th level characters written by Graeme Barber and developed and edited by Kim Mohan. It takes place in a grippili village overrun by yuan-ti that have come to find what secrets are hidden in the temple beyond the village. Two yuan-ti factions are in conflict as they vie to discover what is hidden in the temple.

The characters become aware of the situation when one of the Avowed approaches the characters about a possible problem with a nearby grippli village. Candlekeep trades with the grippli, the frogfolk raises giant crabs that they harvest for meat. The Avowed hires the characters to investigate what is going on. The characters are given the Book of Cylinders that reads like a history of events, but it is a prophetic book that tells of events that are unfolding in the current time.

The characters then head out to the outpost where the grippli trade the crab meat. There they learn from the grippli leader, the Pond Mother, about the two groups of yuan-ti. The first group arrived and asked to excavate an abandoned temple at the site of the grippli’s old village. The two peoples work together to do the work until the second group arrived. The second group attacked the village killing many of the grippli and taking the friendly yuan-ti captive.

The two factions are not that important to the adventure, except the good yuan-ti are used as sacrifices at the temple. It could have been interesting if the players could have used the two factions against each other. Instead, the good yuan-ti are just a small story element that could have had grippli used in their place.

The characters then head out to the village to try and save all of the grippli and good yuan-ti that they can. Their first obstacle is the maze of docks where the giant crabs are kept. The sprawling docks are made perilous by all the starving giant crabs that are getting free from their captivity. Mazes do not work very well in D&D. They look fantastic and inspire awe but they come off as awkward and boring in play. The Crab Maze is a perfect example of this. The tangle of docks looks very cool on the map and the picture on p. 95 is very evocative. In-play the Crab Maze is a group stealth check followed by combat if the stealth check is failed. The DC is so high for the stealth check that failure is almost inevitable.

This whole adventure is combat-heavy. There are elements of stealth that can give the characters an advantage in the combat encounters, but the sword is the only answer to all the questions. To enter the village, you have to kill the guards on the village side of the breakwater. To save the grippli in the Pond Mother’s Home, you have to kill the guards. To save the grippli eggs in the brood pond, you have to kill the guards. There are no battle level maps provided for any of these encounters, so you could create some diversity to the fights by making interesting battlemaps with very different terrain.

 There is so much potential in this adventure that just sort of falls flat. I was excited about the adventure while I was reading it, but in practice, it was a slog even though I cut out most of the combat encounters. The four magic items at the end of the adventure are worth the trip, especially if you swap out the items in the sarcophagus to match your specific campaign. There are good bones to the adventure but you are going to have to do quite a bit of fleshing out to make it fun.

How it Played

I do not know if it is a coincidence, but this is a 6th level adventure and Ghosts of Saltmarsh has a gap at 6th level. The nautical nature of this adventure fit very well into my campaign and was a no-brainer to add Cylinders to Saltmarsh. I used this in conjunction with a homebrewed encounter in the town of Saltmarsh to get my player’s characters to 7th level for Chapter 6: The Final Enemy.

 The trip across the docks was not as harrowing as I had imagined. I also worried that the players would decide to just row around the docks and land on the shore, it is what I would have done as a player. The druid in the party completely forgot that he could speak to animals and never tried to communicate with the giant crabs. It turned into a combat slog across the docks. Adding a story beat where the Pond Mother asks the characters to save their giant crab herd would add to the Crab Maze section. The characters could learn where the food for the crabs is stored and how to operate the gates for the cages. It would turn a combat encounter into a skills challenge.

 The session where we played the Crab Maze section ended after the characters breached the breakwater and killed the guards there. Everyone went home that night underwhelmed by what happened in the session. I ended up removing all of the combat situations in the village between sessions to speed things up. This side adventure was all about the temple for me and I wanted to get the players there as soon as possible.

 The fight at the temple was very good. The players came up with a really good battle plan that went completely out the window in the first round. They were going to draw out the enemy into the courtyard and attack them there. Unfortunately, the players in the group who were not all in on the plan won initiative and charged in forcing everyone else to follow.

 There are several dangling threads that you can continue the adventure if you are interested. Like, what is beyond the debris-clogged stairs that lead below the temple? Where did the yuan-ti come from? Is there something farther down the river? These were not questions that I was interested to answer given how I was using this adventure. Open threads show up in many of the adventures in Candlekeep Mysteries for DMs to continue the story if they want.