Underwater Encounter Combat Terrain, Treasures and Complications for 5e

"There is a cloud of inky black darkness"

Tables for Combat Terrain and Minor Treasures and Encounter Complications for Underwater Encounters. Result is from Underwater Encounter Complications.

Enhancements by terrain - coastal | desert | forest | grassland | hill | mountain | underwater

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Underwater Encounter Enhancements

What makes this underwater encounter different?

There might be a whale skeleton or an area of grasping seaweed. A creature might carry several holy symbols of sea deities or a bead of force. There might be several underwater cave entrances or a hallucinator terrain concealing a chasm.

There is a 5e Underwater random encounter generator at ChaosGen. There is also a pdf of these and more tables at the DM's Guild as Underwater Encounters.

Underwater Encounters Terrain Encounters Bundle for 5e

Underwater Encounter Tables - creatures | locations | non-combat | enhancements

Underwater Combat Terrain

1d8+1d12Underwater Combat Terrain
2 A maelstrom
3 Bottom of a cliff
4 An area of magical darkness
5 A cave entrance blocked sticky seaweed (treat as webbing - DMG pg 105)
6 A whale skeleton
7 A floating pocket of air
8 A column of stone
9 A glyph of warding (explosive runes - thunder)
10 A cage on a chain or half of a wreched ship
11 Grasping seaweed in the area acts as an entangle spell
12 A swarm of inquisitive brightly-colored fish, attracted to any light source
13 A strong current runs through the area
14 An underwater cave entrance
15 A cloud of inky black darkness
16 A forceful current pulls creatures downwards
17 An anchor with a chain leading upwards
18 A deep trench
19 A forceful current pulls creatures upwards
20 A hidden cache (Perception check to spot if near) with oil of slipperiness (or roll on Minor Underwater Treasures)

Underwater Minor Treasures

1d20Underwater Minor Treasures
2 A large green peridot worth 1000 gp
3 Potion of Storm Giant Strength or Potion of Vitality
4 Intricate set of dragonchess with ivory pieces using creatures of the sea
5 Elemental Gem (water)
6 Several sheets of bronze engraved with sea elf ballads in Elven
7 Elixir of Health or Potion of Greater Healing
8 A long reed pipe covered in runes in Aquan and intricate carvings of seahorses. Worth 150 gp
9 Potion of Animal Friendship or Scroll of Protection - Beast
10 An exotic saddle or 100 ft. of silk rope
11 1d4 Potions of Water Breathing or 1d4 Potions of Healing
12 Artisan's tools (mason's tools or alchemist's supplies)
13 Oil of Slipperiness
14 2d6 holy symbols of various sea deities
15 Spell Scroll of control water (or freedom of movement)
16 2d4 waterproof ceramic and glass lanterns capable of working underwater. Worth 50 gp each
17 Bead of Force or Dust of Dryness
18 1d6 pearls worth 100 gp each
19 Spell Scroll of mirage arcana (or telepathy)
20 A hooded cloak with eight tentacles. It is finely woven of rare seaweed and sea-elf hair. Worth 1200 gp

Underwater Encounter Complications

1d8+1d12Underwater Encounter Complications
2 There is a programmed illusion (or mirage arcana) here
3 There are merrow (or roll on Underwater Humanoids) here (or nearby) as allies (or servants / mercenaries)
4 There is a hallucinatory terrain concealing a chasm
5 There is a cloud of inky black darkness or roll on Underwater Combat Terrain
6 There is a hidden item (or cache) here. A Bead of Force or roll on Minor Underwater Treasures
7 There is a whale skeleton or roll on Underwater Combat Terrain
8 There are giant sea horses here (or nearby) as pets (or guards). For alternatives roll on Underwater Beasts
9 There is a strong current running through the area or roll on Underwater Combat Terrain
10 There is a prisoner in the encounter or a lone traveler nearby. Roll on Quick Underwater NPCs
11 There is a wreck here (or ancient sunken settlement)
12 The creatures are carrying a magic item (or it is hidden nearby). Roll on Magic Items - Underwater
13 There is a floating pocket of air or roll on Underwater Hazards and Obstacles
14 There are several underwater cave entrances here
15 There is a swarm of inquisitive seahorses or roll on Underwater Hazards & Obstacles
16 Nearby is a dragon turtle (or pick from Underwater Encounters Level 11+) those encountered try not to disturb.
17 There mass of rotting bodies chained together or roll on Underwater Hazards and Obstacles
18 There is a portal here to the Elemental Plane of Water (or the river Styx in the Lower Planes)
19 There is a second group of creatures nearby (roll again on the appropriate encounter table)
20 There is a shrine to a sea deity protected by hallow (or forbiddance)

More Encounters

There is a 5e Underwater random encounter generator at ChaosGen. There is also a pdf of these and more tables at the DM's Guild as Underwater Encounters.

Underwater Encounters Terrain Encounters Bundle for 5e

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