Disappearance on the Steamboat Augustine

Herein lies a 2-4 hour mystery one-shot adventure optimized for 1st-2nd level party of 4 in the D&D 5e system. It heavily features roleplay and exploration to solve a whodunnit case and is readily adaptable to other systems if an enterprising GM improvises stat blocks for a couple small combat encounters. We are currently playtesting the adventure and updating the layout. The document is partially optimized for screen readers but has a known issue with chapter headings repeating words. Any feedback or player stories are  welcomed!

The adventure was developed through the "Write your first adventure | D&D 5e Path" class by the Storytelling Collective, which I strongly recommend for DM's interested in structure for publishing their own work!

CW: asphyxiation, fish, dark water

~Background

In the Tunico Bayou, it is said that a careful eye can find her under the glow of a full moon. When the air is thick with singing frogs and light ripples into the darkest shade of the cypress trees, she stirs. With a flick of a tail, in an upwelling of water, she emerges: the elusive Moonglow Queen.

The region is sparsely inhabited by several families that go back several generations. Some settled seeking privacy, others arcane secrets, a few more just to live simply off the catfish and sweet moss of the bog. The Moonglow Queen is a potent entity with power over the swamp, inhabiting a giant catfish as an avatar. She punishes those that disrupt the natural balance by feasting on fish of her river when they are large enough to grow souls. Through a process of a little divining and a lot of brutal trial and error, local inhabitants have developed a system of fishing regulations and full moon curfews to avoid invoking her wrath.

A couple months ago, despite the rumors about the bog and its careful natural balance, a cruise line set up shop along the river. News of The Steamboat Augustine pervades the land, from socialites bragging about their vacations to the rabble of the seediest pubs yearning for its culinary delights. However, in the past weeks a new rumor has emerged: a fair few who take the cruise go missing, never to be seen again!

~Playtesting

Thank you for helping me improve this adventure! In addition to making the adventure more broadly engaging, a key goal of playtesting is to dial in the tension of the mystery. I wish to refine it such that players neither immediately discover the culprit nor lack enough information to meaningfully advance their investigation. I wrote a series of events and clues to give you the tools to balance this tension: events may be deployed at your discretion to guide the players while more active players could find themselves preoccupied with clues that they personally discover. Additionally, all NPCs may be interviewed or reveal useful information as players roleplay with them. I am interested in how you use these elements of the adventure to guide your players and what you find most or least effective. Please complete this adventure with your players and fill out the questionnaire provided in this google form: forms.gle/D9pApmxG4fhmoUhTA

Happy travels through the Tunico Bayou!