Worldbuilding Power: Underwater (2019)

From publisher blurb:

Use aquatic realms in character development, worldbuilding, and adventures!

When we think of underwater realms, we often think of Atlantis. The fictional island, first mentioned by Plato, sank deep beneath the sea following a series of violent earthquakes. It’s only in relatively modern times that we’ve imagined survivors, adapting to life beneath the seas and rebuilding their civilization. We have Aquaman, Namor the Sub-Mariner, and the eponymous Disney movie to thank for contributing to that lore.

There’s also the Cthulhu Mythos to draw upon. From the Great Old One himself, lying in his house in R’lyeh deep beneath the Pacific ocean, to the Deep Ones residing in the underwater city of Y'ha-nthlei off the coast of Innsmouth, Lovecraft brought horror to aquatic realms. Science fiction has contributed numerous films about modern man living and working under the sea. For humor, we can always fall back on Spongebob Squarepants.

The point is, there’s a lot of material to mine for underwater worldbuilding. Adventurers will find plenty of opportunities to explore, fight strange creatures, and recover lost treasure. Antagonists will pursue those same things, with a more selfish bent. The rest of the world might be oblivious to the existence of the undersea realms, at least until what dwells below comes to up to menace the surface world.

In this book, we’ll show you how to utilize underwater terrain in your worldbuilding endeavors. You’ll see how it can influence character, setting, and story elements. By the end, you’ll understand how to better utilize underwater realms as essential, useful, and entertaining parts of your campaign.