The first step to any good pirate adventure is finding a ship; after that, it's all about the love of the journey and the conflicts that arise along the way. Coastal conflicts define any hybrid land/sea encounters you’d expect to crop up- having some tools to put together memorable fights will set you up to give your players encounters they’ll remember for years. These tables are here to provide you with inspiration or random encounters to drop on your players and add some more life to the coastal environments in your worlds!

Sources

Each encounter focuses on a monster from throughout the D&D 5e library; to see what book or source they come from, you can consult the Book column. The sources unabbreviated sources are Basic Rules (BR), Monster Manual (MM), Mordenkainen Presents: Monsters of the Multiverse (MPMM), Icewind Dale: Rime of the Frostmaiden (RoF), Out of the Abyss (OoA), Volo’s Guide to Monsters (VGM), Ghosts of Saltmarsh (GoS), and Storm King’s Thunder (SKT).

Coastal Random Encounters

The following table provides random encounters for parties playing in various “tiers” of gameplay; they generally reflect encounters you can sculpt to work for tables within a level range. The Low-tier can work for levels 1-4, Mid-tier for levels 5-11, and the Upper-tier for levels 12+.

Low-Tier Adventuering Random Encounter Table

            d12
            Book
            Encounter
            
            1
            BR
            1d4+3 scared crabs and 1d4+1 giant crabs rising to defend them from people
            
            2
            BR
            1d6+3 blue kobolds returning to their boat to get to their blue dragon’s lair
            
            3
            BR
            1d4+2 merfolk merchants and their giant crab hauler carrying goods for trade
      
            4
            SKT
            1d4+2 sea elves staving off three sahuagin raiders
            
            5
            MPMM
            Two tortle pilgrims on a slow yearly journey to a holy site
            
            6
            BR
            A nest of 1d4+2 harpies on the cliffs above crashing waves full of wrecked boats
            
            7
            MPMM
            1d6+1 sea spawn with varied parts attacking a fishing boat returning to shore
            
            8
            BR
            A druid and their griffon companion scouting the beaches for something
            
            9
            BR
            A plesiosaurus lounging in the sand
            
            10
            BR
            A sea hag disguised as an elderly woman luring people to her ruined beach hut
            
            11
            MPMM
            A mated pair of quetzalcoatlus carrying back mouthfuls of fish for their young
            
            12
            MPMM
            A merrenoloth taking bargained captives to the underworld through a storm

Mid-Tier Adventuring Random Encounter Table

            d10
            Book
            Encounter
            
            1
            MM
            Two sahuagin priestesses and 1d6+2 sahuagin dragging a screaming captive
            
            2
            MPMM
            1d4+3 swashbucklers and their small pirate vessel raiding a merchant boat
            
            3
            BR
            A pair of water elementals rampaging through a small halfling fishing village
      
            4
            MPMM
            Four of deep scions carrying a rare item they’ll use to awaken a monster
            
            5
            MPMM
            A dolphin delighter and its 1d6+3 triton companions going home after a hunt
            
            6
            MPMM
            	A kraken priest leading 1d6+3 kuo-tao lackeys seeking a beached relic
            
            7
            MM
            A sahuagin baron leading a coastal raid with 2d4+1 sahuagin
            
            8
            VGM
            A sea hag nature coven covering a cove in their strangling foliage
            
            9
            BR
            A wounded young bronze dragon halfway up the shore, struggling to breathe
            
            10
            BR
            A young blue dragon razing a pair of ships who failed to pay its tithe

Upper-Tier Adventuring Random Encounter Table

            d8
            Book
            Encounter
            
            1
            BR
            A pair of rocs returning to their nest with a flailing killer whale for dinner
            
            2
            MPMM
            A morkoth and its 2d6+3 sahuagin servants and 1d4+1 sahuagin priestesses
            
            3
            BR
            A storm giant and its two giant shark companions collecting tribute from a town
      
            4
            MM
            An adult blue dragon and its 2d6+3 blue winged kobold and kobold underlings
            
            5
            MPMM
            A blue abishai and its 1d6+3 blue guard drakes hunting an adult bronze dragon
            
            6
            MPMM
            A wastrilith opening a portal to the abyss in a bay to release demons at the coast
            
            7
            MPMM
            A leviathan woken from its slumber attempting to sink a coastal fort
            
            8
            BR
            An ancient blue dragon unleashing its fury on warships charging its lair