In Part 1, I reconfigured the Manor House from U1 Sinister Secret of Saltmarsh. In Part 2, I adapted the Sample Dungeon from Holmes Basic. Next, I took the excised map sections from both and created a Sea Caves level. Part of this level (the explored part) serves as the pirate base. Another dungeon level—derived from Zach Howard's excellent Forgotten Smugglers' Caves—exists between the Dungeon level and the Sea Caves, and I incorporated several areas from that into the Sea Caves level as well. I'll cover the full FSC level in an upcoming post.
By this point in the campaign, I had a pretty solid sketch map of the bluff's macro-area, showing the exterior orientations/positions of the house, the tower, the gardens and estate wall, and the not-so-obvious areas such as the sea cave entrances and a "muddy mound" in the salt swamp below the bluff.
More importantly, by the time I got to mapping out the Sea Caves level, I had already shared the sketch map with the players, who did a really good job scouting out the whole area before delving too deep. This locked in the positions of certain sea cave entrances that had to connect with the finished Dungeon level map.
To start with, I took the bluff coastline from my sketch map and aligned it to the 4:1" grid on a blank Photoshop canvas (24" x 24", 7200 x 7200px). Then I took the sea cave segments I carved out of U1, the Sample Dungeon, and FSC, and aligned their grids to my map grid. I then reoriented and repositioned the segments to fit the bluff layout.
I wanted the U1 sea caves to point west, to match the repositioned west wing of the manor from which the pirates signal their ship and guide the longboats into shore. I also increased the map scale for the U1 piece from the
original 5' per square to 10', same as with the manor maps, to open
the spaces up a bit. Green arrows indicate where the original sea caves will connect with the sea.
Here's what the "starting map" looked like when I was done:
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| Sea Caves Conversion – Map 1 (scale = 10') |
The lighter gray area in this map represents the ground mass in which the caves exist, while the darker gray area represents open sea. The gaps in the coastline are sea cave entrances, several of which have already been sighted by the party (and one of which had been superficially explored via rappelling from the cliff above).
Being at the base of the bluff, the Sea Caves level occupies much more ground than the levels above, making for a larger map area. This gives me a lot of room to expand the pirates' operation, add in new (unexplored caves), and build connections to other sections of the overall dungeon, including to the naga's lair from N1 Against the Cult of the Reptile God, which I have integrated as simply another section of the ancient subterranean complex Zenopus was exploring. The "muddy mound" in the swamp is the entrance to the naga/troglodyte lair.
In the original Sample Dungeon, the sea entrance to area M lies off the map: "to the west about 500 feet." Obviously, the cave now faces south, but I reduced the length of the sea tunnel to ~100 ft. The sea cave in U1 (area 30) "opens directly to the sea," so I set the fragment right at the bluff's edge. In the main entrance to FSC, the back of the seemingly dead-end cave is a tunnel, mostly concealed by "a pile of boulders, coated in barnacles and seaweed, that rises from the water line."
To entice the players to explore the FSC area, I put the pile at the back of an unusually-long (100') sea cave. This also gave me some extra padding space for the FSC map, which I had to really cut up and spread out to fit the larger area and connect properly with the levels I'd already finalized. A final change to this portion of the FSC map: In the original, the wereshark's lair (area 10) sea entrance was underwater, and his lair is difficult to find from the dungeon-side as well.
He's such a great NPC though, so I wanted to increase the chances of the party encountering him. I connected his main sea access to one of the sea cave entrances instead. The party has already discussed renting boats to explore the sea caves on multiple occasions, so there is a good possibility they will meet him. If they don't kill him, I intend for him to be able to provide some aid to the party, including info about the fish-folk society that once lived in these caves. There will also be a way on this level to cure the lost sailor of his wereshark curse and allow him to return to his family in the town of Saltmarsh.
The Sample Dungeon says nothing about the effects of tides, but both U1 and FSC do, so I established high water marks for all three entrance caves, and made the entrance to the wereshark's lair navigable only at low tide. All other sea cave entrances (at the moment) are shallow, dead-end spaces with nothing of interest. I've thought about developing a new, submerged level located below the Sea Caves level and accessed via these "dead-end" caves, to further explore the fish-folk material from my expansion areas. I have no immediate plans, however.
Once the pieces were in place, I redrew new outlines for them. Zach created his FSC cave maps using an abstract, flowchart style (in Excel, I think), which is a clever, functional approach that is easy to parse at a glance. I often use a similar, hand-drawn approach to sketching out a dungeon design, usually squares for rooms and circles for caves, with lines in between. It's a great visualization tool. But I like to draw, too, and I often run on VTT, so I always create finished, dimensionally-accurate maps. In this case, I turned his abstract boxes and lines into rough, curving tunnels and cave walls, but kept the dimensions as close to the original map as possible.
In addition to these dungeon pieces, I added three other known connections to the upper levels: the cellar stairs from the manor (area M21), the pit shaft from area D2j on the Dungeon level, and the staircase from D26, also from the Dungeon level. From these now-fixed points, I'll be adding new caverns and tunnels, and adapting the original dungeon keys. I'll also connect this level with the troglodyte caves in the naga's lair from N1 (to the east, off this map). Unlike the other levels, most of this level key is my original material.
I darkened the bluff background to match the Dungeon level and nudged some of the FSC locations to fit the map better. With the new outlines drawn, the starting map now looks like this:
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| Sea Caves Conversion – Map 2 (scale = 10') |
My next goal for the map was to connect the three pirate/smuggler areas: both sets of sea caves and the staircase up to the manor's cellar. The antagonists were "smugglers" in both original adventures, but making them"pirates" gives off a more direct, predatory vibe. It's a subtle difference, but my players will key in faster to taking on pirates than they will smugglers (who might just be minding their own business while skirting the law).
To accomplish this, I'll need a passage and series of caves to cut diagonally across the map. This will leave me with a big map section to fill to the north and east, and two smaller map regions to fill in the center and west. The big map section will be an area of caves as yet unexplored by the pirates, that connects to a bizarre temple to a piscine god in the west, via some flooded tunnels and chambers in the center. The unexplored caves will also feature some troglodytes, servants of the naga who are here to kidnap pirates (and adventurers!) to bring as offerings to their queen. This section will also be where the Sea Caves level connects with the N1 dungeon (area N19).
After a few rough sketch attempts and some trial-and-error, I ended up with this expanded Sea Caves map:
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| Sea Caves Conversion – Map 3 (scale = 10') |
My level key is quite long since much of this material is either customized from the original or created from whole cloth, so I'm putting all of it behind the cut.
