Underwater Adventures in Dungeons & Dragons

The Player’s Handbook, Dungeon Master’s Guide, and Monster Manual all provide great resources for underwater or ocean-based D&D campaigns. Today I’ll run through the Dungeons & Dragons Player’s Handbook to help you dive into your underwater adventures.

Classes

Many of the classes presented in the Player’s Handbook can be customized to suit an ocean campaign. Druids can choose creatures with a swimming speed for their wild shape ability from 4th level, while rangers can choose appropriate animal companions to suit to underwater adventures.

Backgrounds

The following backgrounds work well for an ocean campaign:

Acolyte. Many of the deities of the Forgotten Realms are worshiped in their ocean aspect by seafarers and fisherfolk or given offerings in hopes of a safe sea voyage. A character with the acolyte background may have served in a seaside temple or as a ship’s chaplain. Amphibious characters might tend to the needs of an underwater community or maintain sunken temples and shrines to ocean deities.

Criminal. A character with the criminal background might be a pirate or an escapee from a prison ship. Many criminals find their way into shipping ports, in the hopes of finding a ship to take them to wealthy cities. Amphibious characters are much like their land going counterparts.

Guild Artisan. A character with the guild artisan background might be a cartographer, a shipwright, or a traveling artisan from a port city or island town. Guild merchants are particularly common in port cities and aboard ships. Amphibious guild artisans might be jewelers working in pearl and shell, coral carvers, leatherworkers, skinners, or scrimshaw carvers, besides a host of other occupations.

Hermit. Hermits can be found inhabiting ocean caves, beachcombing along coastlines, and on remote islands. Some hermits are castaways who’ve come to enjoy their life away from the stresses of society.

Outlander. A character with the outlander background might be a fisherman, a pearl diver, a seafarer, or even a pirate with a love of adventure.

Sailor. Both the sailor and the pirate variant backgrounds are excellent options for an ocean campaign.

Equipment

The Mounts and Vehicles section of the Equipment chapter includes a list of waterborne vehicles. The Services section lists a ship’s passage as costing 1 sp per mile.

Abilities

Strength (Athletics) checks are used for swimming in stormy seas or raging rivers, or if you’re struggling with a creature while in the water.

Adventuring

The Special Types of Movement section covers swimming, while The Environment section covers suffocating, vision and light, and food and water. The sun’s light only penetrates so deep below the water, and ocean water is undrinkable, meaning that characters must find a source of fresh water or rely on magical means for survival.

Spells

Alter self, create or destroy water, any spells that create light (light and daylight), water breathing, and water walk are particularly useful spells for underwater adventures.

Many spells have uses that might not be obviously apparent at first, such as using forcecage to create an air bubble. Rope trick, because of the opening it creates being at the bottom of the space, creates a very functional refuge that won’t flood.

Spells that often see use in a land-based campaign might be less useful in a water-based campaign, while spells like fireball might have little effect underwater, but can be devastating if hurled at a wooden ship.

Creatures

Appendix D contains a number of fitting creatures for your sea campaign:

Consider the constrictor snake (which could double as an eel with a faster swimming speed), crocodile (saltwater crocodiles can use the same statistics), poisonous snake (with water breathing for sea snakes), and the reef shark.

Skeletons and zombies might be drowned sailors, cursed pirates, or undead merfolk (with the addition of a swim speed).

Next week we’ll look at the Dungeon Master’s Guide as we continue to build our ocean campaign for underwater adventures.