5e D&D Combat Encounters - Underwater

Combat Encounters include creature groups, hazards and lone npcs. Maybe a lost lizardfolk, a forest fire or a talkative druid
Encounters underwater bring visions of murky seas, vast reefs and dark depths. They might occur in a kelp bed, an underwater cave or by a long-forgotten shipwreck

tools for - dnd5e encounters underwater

level: party size: terrain: sources: type:

combat

2 Giant Sea Horses

At a pile of seaweed surrounded by shells (the marine wildlife has disappeared)
They are strong swimmers (extra speed)
In a fight they fight to the bitter end
Possibly... they have 2d6 holy symbols of various sea deities
Difficulty... 300.0 Hard

combatwater

1 Ice Mephit
1 Mud Mephit (Monster Manual p.216)
1 Steam Mephit

At an eroded coral-carved hall (which is associated with a mysterious sahuagin)
They are watching something from the surface
In a fight they attempt hit and run tactics
Possibly... during the fight a section of floor or ground gives way
Difficulty... 400 Deadly

combat

1 Giant Sea Horse

At a patch of black sea mushrooms by an eroded statue (nearby is a carved rock)
They are telepathic
In a fight they run and hide if things go badly
Possibly... they have a suit of Mariner's Armor
Difficulty... 100 Easy

combatseamonster

1 Merrow

At a damaged seaweed bed (nearby is the fresh corpse of a crab)
They are exploring a wreck
In a fight they combine ranged attacks at the most heavily armored foes
Difficulty... 450 Deadly

combatsnake

A nest (group) of snakes

1 Giant Constrictor Snake
1 Constrictor Snake

At a broken cliff (the area is associated with whales)
They are exploring a wreck
In a fight they surrender if things go badly
Possibly... they have a Trident of Fish Command
Difficulty... 750.0 Deadly

combat

1 Merrow

At a part-buried stone mosaic (by an area of soft coral)
They are a shapechanger
In a fight they focus on anyone with religious icons
Possibly... they have a Bag of Holding
Difficulty... 450 Deadly

combatwater

1 Water Weird (Monster Manual p.299)

At a seaweed garden surrounded by shells (there is the body of a humanoid)
They are a shapechanger
In a fight they focus on any obvious spellcaster
Difficulty... 700 Deadly

combatseamonster

1 Plesiosaurus

At a pillar of stone and a cave entrance blocked by sticky seaweed (a noticeable current pulls creatures downward)
They are bearing symbols of a deity of the sea
In a fight they fight to the bitter end
Difficulty... 450 Deadly

combatwater

1 Water Weird (Monster Manual p.299)

At an area of algae and a wide trench (near a large pocket of air)
They are preparing to go to the surface
In a fight they surrender if things go badly
Difficulty... 700 Deadly

combat

1 Giant Sea Horse

At a steep slope. There is a narrow underwater cave entrance with a damaged seaweed garden (there are signs of a flying fish that look fresh)
They are exploring a magical portal
In a fight they attack whoever is causing them the most pain
Difficulty... 100 Easy