For my past columns about using D&D Fifth Edition sourcebooks with Freeport: The City of Adventure, see the Freeport 5E Index.
This columns contains spoilers for the adventures in Ghosts of Saltmarsh.
Ghosts of Saltmarsh is a nautical-themed anthology of seven adventures from previous editions of D&D updated to the Fifth Edition rules. Three of these form the original Saltmarsh trilogy (The Sinister Secret of Saltmarsh, Danger at Dunwater, and The Final Enemy), so the book begins with a much expanded description of that port town. The appendix includes rules for ships, sea travel and encounters, and a few additional encounter locations that are too short for chapters of their own.
This book should be invaluable for a GM running a Freeport campaign using 5E. Some adventures will be easier to adapt to that setting than others (see each chapter's entry below), but almost everything in the appendix will be useful in any maritime campaign.
Saltmarsh
Saltmarsh is a coastal port town with a sizable fishing fleet, but it also serves as a port of call for many merchant traders. It is a far cry from the cosmopolitan, pirate- and cult-infested island city of Freeport, so the three Saltmarsh adventures in this book will require some thought to fit into a Freeport campaign.
Perhaps the easiest option is to locate Saltmarsh on the Continent, some days' sail from Freeport--but that make the campaign more about the Saltmarsh region than about Freeport, at least for the duration of those adventures. On the other hand, Saltmarsh could be very useful for fleshing out part of the Ivory Ports part of the Continent, for when your Freeporters are passing through and catch a whiff of interesting news and rumors that cause them to tarry a while.
This chapter also includes a few new backgrounds for PCs--fisher, marine, shipwright, and smuggler--that are perfectly suited to a Freeport campaign. Each of the backgrounds from the Player's Handbook gets a few notes about how to tie them into Saltmarsh, which may inspire similar connections for Freeport GMs.
The Sinister Secret of Saltmarsh
The first Saltmarsh adventure involves investigating a seaside haunted house outside the town, then taking on the crew of a smuggling ship using the site as cover. This is a classic adventure, perfect for starting characters, but difficult to work into a campaign that starts in Freeport. It probably works best if set elsewhere in the Serpent's Teeth, perhaps near Libertyville or one of the handful of plantations on the islands. The house and the ship can also be easily used separately, if the GM needs a creepy hideout or a low-level ship's crew for their own adventures.
Danger at Dunwater
The second part of the trilogy is easier to adapt to a Freeport game. The adventure takes place within a massive lizardfolk lair located in a swamp. Lizardfolk are known to live in the Serpent's Teeth, and a tribe of this size would certainly pose a potential threat to other settlements there (though probably very little to Freeport itself). The other races present for the emerging alliance are also common to the seas near Freeport.
The new lizardfolk stat blocks in the Appendix should be useful in converting older adventures such as "Dead Man's Chest," in Tales of Freeport.
Salvage Operation
This adventure is easily dropped into any ongoing nautical campaign, and Freeport has no shortage of desperate merchants who need adventurers to do dangerous work for them. Demonic cults are also a staple of Freeport campaigns, though GM who wish to emphasize the World of Freeport over Wizards of the Coast's IP may wish to have the villain of this piece worship the alternate Spider Queen described in Green Ronin's Plots & Poison: A Guidebook to Drow.
Isle of the Abbey
The heroes are hired to clear out evil clerics and undead that guard an abbey, while the cult is weakened from a pirate raid. Much like the Freeport line does, the adventure leaves the identity of the cult's god open-ended, with a few campaign world-specific suggestions given in the "Placing the Adventure" sidebar.
The Final Enemy
In many ways, the finale of the Saltmarsh trilogy is the easiest to incorporate into a Freeport campaign. The sahaugin fortress is located some distance from the city, and could easily be located on an obscure reef near the Serpent's Teeth. The "sea devils" (as Freeporters call them) are a perennial problem for the City of Adventure, so scouting and then assaulting the site would be a highly appropriate mission for Freeport-based heroes. The module presents the stronghold as a former lizardfolk lair, but in the World of Freeport it might actually be an ancient Valossan ruin.
This adventure also includes many new stat blocks for new sahaugin foes and other undersea monsters (in the Appendices) that Freeport GMs can make use of elsewhere--for example, in converting the sahaugin attack in Crisis in Freeport.
Tammeraut's Fate
An island hermitage has come under attack by undead pirates, and by other monsters drawn to the scent of death. Once the PCs secure the island, they must follow the undead below the waves to stop the real threat that they pose.
The Styes
The Styes is a decaying port slowly sinking into the sea. Overall, the City of Adventure is too prosperous to be a good match, but the major sites of the adventure could be probably be transplanted to the docks of Scurvytown. Mr. Dory might be a gang leader, or a politician with ties to a member of the Captains' Council. The Tharizdun cult might be recast as a followers of one of Freeport's secret cults, such as the Unspeakable One, the Crawling Chaos, or Yarash. This adventure is certainly the most Lovecraftian in feel in the anthology, so may very well be worth the extra effort to adapt to Freeport.
Of Ships and the Sea
The book's first appendix presents rules for ships and ship combat, sea travel, and water hazards. Tables for generating random encounters, ships, and mysterious islands are also included. Finally, a trio of underwater locations are briefly detailed.
Magic Items
A handful of new magic items are presented here, including a couple classic items updated from older editions of D&D.
Monsters and NPCs
In addition to the new monsters already mentioned above, this appendix includes a number of new undead and constructs that should prove useful in other adventures in the "sword & sorcery" vein of Freeport.
