D&D 5e · 100 scenarios · Roll d100 → roll D1
A complete D&D 5e random encounter table for ocean scenes. Roll a d100 to pick a set, then roll a D1 to pick a scenario within that set — 100 unique D&D encounter scenarios in total. Every scenario is system-neutral and runs on either the 2014 Player's Handbook or the 2024 D&D revision. Pair each scenario with a stat block from our D&D monsters catalogue and you have a session-ready encounter in under a minute.
The ship is drawn toward an underwater volcano threatening to erupt. The heat has awakened a dormant water elemental seeking help to relocate a sacred relic. The players must work together to navigate the dangerous terrain and safely move the relic, quelling the elemental’s unrest.
The players come across a mysterious ship that is sailing towards them at high speed. As it gets closer, they realize that it is a ghost ship, crewed by the undead who are cursed to sail the seas for eternity. Once boarded, the players must figure out a way to lift the curse or risk being trapped on the ghost ship forever.
The ocean becomes choppy, two giant sea serpents spot the ship and begin chasing it.
The players stumble upon a sunken ship that has been turned into an underwater tavern by a group of aquatic dwarves.
A merchant ship flies the flag of a nation from a hostile nation. The merchant captain will attack the party unless he gets paid.
A kraken surfaces next to the ship, its massive tentacles ready to crush the vessel. The players must come up with a clever plan to escape or defeat the beast.
A beautiful mermaid swims up beside the ship and asks the players to save her from a giant shark that is attacking her. She will reward players with a necklace that is actually cursed, causing their skin to become fish scales in 1d4 days if they don't get it removed by a cleric or magic-user before then.
While exploring a coral reef, the party comes across a sunken ship filled with treasure. However, the ship is also home to a group of merrow who will do anything to protect their newfound riches. The party must fight their way through the merrow and claim the treasure for themselves.
A huge pirate ship is seen in the distance. A large, dark shape is seen on deck. It's a giant sea serpent! The demon on the front of the ship is laughing and shrieking. The demon is wearing a red cape and has a huge, ornate trident. The ship is sailing towards the party's ship.
A ghostly ship is seen on the horizon, only to vanish moments later.
The ship encounters bioluminescent algae again, creating a ghostly glow.
You sense a powerful magical presence in the water and upon further investigation, you discover a portal to a different plane of existence has opened beneath the waves.
A group of pirates attempt to board the party's ship, but they are actually former slaves looking to free their brethren from a nearby slave camp. Will the party help them in their quest for freedom?
A group of 3d10+3 sailors attack the group.
Sailing through a field of giant clam shells, they find themselves near an advanced underwater bazaar run by an ocean-tiered merchant named Dampbottom who needs the adventurers to mediate a fierce dispute among competing traders.
The players come across a group of mermaids who are being held captive by a sea hag. The mermaids beg for the players' help in defeating the hag and freeing them from their underwater prison. But the hag may not be as easy to defeat as they think.
The lookout spots a deserted island with an abandoned campsite.
The lookout spots an uncharted island covered in dense fog.
Sailing a ship along the ocean, the players spot a sea monster swimming towards them. They can ask the monster questions using a 10-word maximum.
A giant whirlpool appears in the distance, threatening to consume the entire ship. The party must find a way to escape its pull or risk being sucked into the depths.
An abandoned ship floats in the ocean with its sails torn and mast broken. No one is on board this ship, but there are many bottles lying on the deck of the ship that are stamped with the name 'John' and 'Jack' on them, as well as a bottle with 'Jane' on it and one with 'Jill' on it. There are also two barrels labeled 'Johnny' and 'Jenny.'
The players see a group of mermaids playing and singing on the shoreline, but upon closer inspection, they realize that the mermaids are actually sirens who are luring unsuspecting sailors to their deaths.
The players come across a small island with a lone mermaid sitting on the shore, crying. She tells the players that her lover, a powerful sea god, has imprisoned her there. The players must either help the mermaid escape or risk angering the sea god.
The party encounters a ship containing a single sailor. He dives overboard and swims away when he sees the party coming. The ship is later discovered to be a ghost ship.
A sudden and unusual wind blows from an unexpected direction.
The ships are approaching a giant rock in the middle of the ocean. The rock is actually an island, and it's home to a giant creature. The creature will politely ask to eat one of the ships. If refused a single ship, it will attack them all. The thing is almost as big as the island itself. Wait... the island IS the creature...
A mysterious figure appears on the ship and reveals that they are actually a powerful sea witch. The witch offers to grant the players a wish, but at a steep cost. They must decide whether to accept the offer or risk angering the witch.
A mysterious figure on a small boat appears in the middle of the ocean. The figure is revealed to be a powerful wizard who offers to transport the players to a distant island in exchange for their help in defeating a powerful sea monster that has been terrorizing the nearby waters.
The players come across a group of stranded sailors, desperately trying to repair their ship before a powerful sea storm hits. The players can choose to help the sailors or take advantage of their misfortune and steal their ship.
A storm comes out of nowhere! It's a real doozy! The captain of the ship isn't sure if they can survive it!
The party comes across a peaceful village of gillmen who have been terrorized by a group of water elementals. The party must work with the gillmen to defeat the elementals and free the village from their grasp.
A thick fog bank sets in, muffling sounds.
A group of mer-men approach the party's ship and ask for food. If they get food, they will attack the party. If they don't get food, they will ask for gold or passage to another land. They will attack if denied passage or gold.
The party's ship is becalmed in the middle of the ocean, and they are running low on supplies. They must find a way to survive until a powerful storm hits and transports them to an underwater city inhabited by a friendly race of merfolk who offer to help them on their journey.
A group of sea turtles surround the ship and guide the players to a hidden underwater grotto filled with treasure. However, the players must solve a series of puzzles to unlock the grotto's entrance.
A merchant ship is being attacked by a kraken and the ship's captain has been killed. The ship's crew has asked for help from the players.
You see a pair of sea lions lounging on a rocky outcrop.
A group of pirates have been stranded on an island after their ship was sunk. They've got a treasure map, but they don't know how to get back home.
The players encounter a sea witch who offers to grant them a wish in exchange for completing a dangerous task for her. But the wish may come with a dangerous price.
The ship is attacked by a group of pirates who want to steal the ship and sell it for a profit.
A ship approaches, but it has no sails and no oars.
The party comes across a mysterious island that seems to have magical properties. They discover that it is protected by a powerful elemental guardian who only allows certain individuals to enter. The party must pass a series of tests to prove their worth and gain access to the island’s hidden treasures.
The party sees a huge creature rising from the water. It's dripping wet and covered in slime. Its head is like a spear, attached to a long neck and a long tail. Its body is like a giant tear, with huge eyeballs and tentacles sprouting from it. It rises up and starts firing its eyeballs at the party. If you are looking for a way to end the adventure early, this is a great way to do it. As ridiculous as this creature sounds, it is allowed in the game.
A group of merfolk attack the ship! They want to steal the ship, sink it, and then collect more gold from the insurance policies on the ship.
A pirate ship fires its cannons at the players' ship. The ship is badly damaged, but no one is hurt because all of the players are below deck except for one who is standing on the stern of the ship watching for other ships.
The ship encounters a stretch of water populated by bizarre, luminescent creatures under the control of an eccentric aquatic gnome inventor named Tinkerdrop. He seeks rare reagents to finalize a device that can provide limitless freshwater.
The crew discovers a case of fine wine on a tiny island.
A log drifts by, covered in barnacles and seaweed.
Muffled cries of distress carry to the players, who decide to investigate. They discover a shipwreck, and in it a treasure chest. They also find an injured sailor, and a giant sea serpent. The serpent attacks the party, but it is injured as well. It swims away, and the party helps the injured sailor.
A group of 3d10 pirates are sitting on a beach, hiding from a storm that is coming in. They are watching for ships to pass by so they can attack them when they pass by.
A ship approaches the ship. It is an elven ship, the only one in the ocean. The elves are looking for something.
A sudden, mystical fog rolls in, creating a phantasmal maze at sea. Each path in this maze represents a different moral dilemma, and only through group discussion and united moral decision-making can they find the true path forward.
A merchant ship approaches the ship the players are on. It's flying a black flag depicting a skull and crossbones. It's looking for a fight.
A giant kraken attacks the ship, demanding a tribute of gold from the players. If they don't comply, the kraken will drag the entire ship to the bottom of the ocean.
A mirror-like calm overtakes the sea, revealed as an illusion created by a reclusive sea mage testing intruders. The mage provides tasks requiring group insight, trust, and unity to overcome, offering powerful oceanic artifacts as rewards.
The crew finds a piece of wood with strange runes carved into it.
A large bird carrying a message lands on the ship's deck. The bird is a messenger from the King. It will tell the players that the king has been captured by slavers and he needs their help.
The players spot a group of dolphins swimming and playing around the ship. However, the dolphins are actually spies of a Kraken who is planning to attack the ship later. The players must either come up with a plan to defeat the Kraken or risk becoming its next meal.
The party's ship is becalmed in the middle of the ocean, and they are running low on supplies. They must find a way to survive until a powerful storm hits and transports them to an underwater city inhabited by a friendly race of merfolk who offer to help them on their journey.
The players spot a group of friendly mermaids swimming nearby. However, they soon discover that the mermaids are actually sirens using their disguises to lure in unsuspecting sailors for their meal.
A group of sailors are stranded on a deserted island after their ship was destroyed by a giant octopus. They plead for the players' help in defeating the octopus and finding a way off the island. But there may be more to the sailors' story than meets the eye.
The party finds a small island with only one lone cottage on it. They see smoke rising from a chimney and decide to investigate. As they approach, they see an old man sitting on the porch, staring out at the ocean. He introduces himself as Quinn and invites the party in for dinner. As they eat, he tells them stories of the olden days and about his magical abilities. The party may choose to stay the night, but they may discover that Quinn is actually a powerful sea hag and has sinister plans for them.
A sudden gale forces the crew to adjust the sails quickly.
A group of 4d6+4 kobolds attack the group.
You sense something large and powerful moving under the surface of the water. Suddenly, a giant octopus emerges, its tentacles thrashing in the air. It seems to be protecting something and will attack anyone who gets too close.
The ship sails into waters with an unusually pungent smell.
Sea serpent. A sea serpent that's been set up on a course to attack the players' ship.
A lone albatross soars gracefully above the ship.
A merchant ship approaches you. The merchant ship is selling goods. The merchant ship is selling really bad goods.
The ship is attacked by a group of pirates led by a half-elf named Justinian.
A group of sirens try to lure the players towards the rocky shore with their enchanting voices. They must resist the temptation and make a quick escape before the sirens' spells take hold.
A group of merchants are transporting a valuable statue, but they've got another shipment at sea that's being attacked by pirates.
A portal to the Elemental Plane of Water appears in the middle of the ocean, bringing with it powerful water elementals and other creatures. The players must close the portal before the elementals take over the ocean and the material plane.
The players encounter a giant whale, trapped in a fishing net. They must decide whether to free the whale or leave it to its fate, as doing so may attract the attention of powerful ocean predators.
A merchant ship approaches. It is flying a foreign flag. It is a merchant ship from a nearby island nation ruled by goblins. The captain of the merchant ship will trade for slaves and prisoners, but he will not trade for anything else
A small rowboat approaches carrying two peasants from one of the nearby islands in this chain. One of them is injured, with an arrow sticking out of his leg. The other one says something about lizardmen attacking them while they were out gathering fruit from one of the tropical islands in this chain of islands.
A group of giant crabs start attacking the ship, trying to protect their territory. The players must find a way to either appease the crabs or defeat them in order to continue their journey.
A friendly sea serpent approaches the ship and offers to guide the players through a treacherous underwater cave system, filled with valuable treasures and powerful sea monsters. But they must be quick, as the serpent can only hold its breath for a limited amount of time.
The crew sees a distant storm brewing and prepares for rough weather.
You see a pair of sea lions lounging on a rocky outcrop.
The water grows murky as they are surrounded by an army of camouflaged sea chameleon warriors. Their leader, a commanding chameleon named Chroma, requests aid in repelling invaders attempting to plunder their secret treasures.
While exploring a submerged ruin, the party encounters a gargantuan sentient crab named Clack'r who has been placed as a guardian by an ancient civilization and needs help uncovering the artifact he's sworn to protect.
Passing through a narrow strait, the ship narrowly avoids rocks.
The players are invited to a party on a massive floating barge owned by a wealthy noble. However, the noble is secretly a vampire who plans to turn the players into his undead minions.
The players come across a deserted island, home to a group of intelligent apes. The apes offer to help the players in exchange for their help in defeating a rival tribe of apes.
A friendly storm giant appears and offers to guide the ship through a dangerous storm in exchange for a favor, which he will collect at a later time. The favor could be anything from retrieving a specific item to completing a task for him.
A large creature with dark green skin floats by in the water. It has tentacles like an octopus's arms, but they're very long arms, reaching down 50 feet below the water level. If a player gets too close to it, the tentacles will grab the player and pull him beneath the water.
The players discover a sunken ship filled with treasure, but it is guarded by a group of undead pirates who will stop at nothing to protect their booty.
A ship approaches the ship, and the captain offers to trade with the party.
The players come across a huge coral reef that seems to be moving and twisting in unnatural ways. They soon realize that it is actually a giant sea creature, camouflaged as a reef.
The wind abruptly changes direction, impacting the ship’s speed.
A water fissure nearly splits their ship in half, revealing an undersea kingdom that’s collapsed. The kingdom’s prince, Kelddan, needs help uncovering traitors responsible for the ruin and saving his subjects.
A ship is sinking in the ocean. A group of merfolk are trying to save as many people as they can. They will ask the players for help.
The lookout spots a formation of rocky pillars rising from the water.
A lunar eclipse is witnessed from the deck.
The crew discovers a peculiar wooden totem floating on the water.
A group of mer-men approach the ship and ask for help with a problem in their village. If players help, they discover that the mer-men are being attacked by a group of hostile sea elves who will not let them trade with the surface world.
A group of sirens attempt to lure the party's ship onto the rocks with their enchanting voices. The party must make a save against their hypnotic melodies or risk crashing their ship.
A deserted island is found, seemingly untouched by civilization. However, as the party explores, they realize that the island is actually a living creature and must find a way to escape before it submerges back into the ocean.
The players come across a mermaid who has been cursed by an evil sorcerer and is now half-human, half-fish. She begs the players to help her break the curse and offers to guide them to a powerful wizard who might be able to help.
A random encounter scenario is just the start of a scene. Pair it with a creature from our D&D 5e monsters catalogue (3,000+ monsters with full stat blocks), an NPC from our pre-built D&D NPC roster, a spell from the D&D 5e spell list, and a reward from the D&D magic items catalogue — and you have a full one-page session ready to drop on your D&D 5e or 2024 party.
Other dice tiers for the ocean: D4, D6, D8, D10.
Want a different setting? Browse all 41 D&D encounter locations — from arctic plains to elemental planes, every D&D 5e location has its own table on Doungim.