What kind of encounters might occur during a journey down an underground river?

What kind of encounters might occur during a journey down an underground river?

After passing a big sign urging you to turn back and that there's nothing worth risking your life down there, you see a skeleton nervously clutching a treasure chest full of gold.

Drowning.

Creepy cave monsters mixed with creepy sea monsters.

Watch the Caves episode of planet earth and make everything giant.

>giant bats at the mouth
>giant axolotl
>giant glow worms that dangle sticky threads to reel in prey
Maybe the stalactites are dripping acid that the party needs to steer around

Blind white worms.

ropers
those stalactite monsters that fall down on you
underground rapids
a secret entrance into Skullport
spiders
water weirds
the river narrows and you see dwarves coming down the other way and there's only enough room for one boat
waterfall(s)
giant fish that eats boats
poisonous gases
a tollbooth run by an undead dude
a dead end
a goblin city
bones strewn everywhere
the other side
a ghost that possesses a party member
the party temporarily crosses into the Underdark or similar plane
a voice calling for help in a side passage

none of these are good ideas

Pirates

Kobold warren who have a set their colony up on some stilts above the water and have dedicated themselves to the service of their aquatic dragon master (a large aquatic monster of some description who they have mistaken to be a dragon that lives in the water.) Once the party kill the dragon the kobolds will feel like a bunch of idiots and set out to leave the cave to set up their struggling colony in a less hostile environment.

Could be made interesting with an urgent danger like monsters in the water.
Meh.
I like this.
the dwarves, poison gas and ghost are all great.
I love this idea to death. most PCs would just go full murderhobo on the kobolds though on first sight.

Leaving the boat.

CEILING!

Bonus points if the kobolds stay in contact with the adventuring group, considering them "good friends and allies".

Extra bonus points if the kobolds end up successful enough to straight out hire the adventuring group to solve a problem for them later on.

Extra extra bonus points if their new colony turns out to be near a breeding ground of the former monster.

bats
crumbling tunnel
underwater monster
boat starting to sink
studd falling from ceiling
drowning
labyrinth

A kindly old ferryman who will take them out of this fucking river the way the came if they're boat's all torn up. He wants 2 pieces of silver for each party member.

They're each carrying thousands of gold and small amounts of copper, but zero silver.

Sounds like that skeleton needs a friend.

Bump

Hey, I used this in my campaign! Either I know you or there is nothing new under the sun.

Definitely the latter, mate, because I've never seen it used.

>those stalactite monsters that fall down on you
Piercers

Telluric storms spewing lightning from the walls.

Flowstone floods which 'amberize' anyone caught in their path.

A giant eyeless white eel with electrical attacks and electrosensivity. It will look like a huge maggot.

Geode-clams.

Pic related.

>Could be made interesting with an urgent danger like monsters in the water.
Different user, but that sounds like it would ruin it. Sometimes the most memorable challenges aren't combat. The most fun my players ever had was escaping a building they set on fire.

bump

the urgent danger is already present: fucking drowning
not everything needs to be hack n slash shit

Underground lizardmen

The travelling dead.

All underground rivers eventually converge to docks of the City of the Dead.

he sun the

THESUNTHESUNTHESUNTHE

Blind stuff like worms, bats, ants. Or just invent some kind of exotic ancient lake creature that has been extinct but somehow managed to survive underground.

>something that suddenly flashes extremely bright so that the party who's eyes have adjusted to the low light are immediately blinded
>blood sucking bats but small enough to be hard to target with attacks and can pass undetected in the gloom

Blind Dagon-worshipping kuo-tua tribe. Make it so the players can watch one of their rituals from afar and then as their boat approaches they notice that the ritual appears to be working...

Deep crow! DEEEEP CROOOOW!

The Cavern of Cocks. It's filled with Penis Stalagmites and penis stalactites dripping with life giving fluids (cum). Occasionally some stalactites fall. It's inhabited by a rare subspecies of ropers. There is rumoured to be a fertility shrine hidden within.

>2 pieces of silver for each party member

Before they give it to him, the ferryman makes an odd request. They have to get another party member to put the coins on their eyes first.

A meeting of a young teenage boy, traveling with his drow companion on a raft. The boy can't speak the drow language, and just calls his companion Jim.

Penis illithid or AssFlayers. They are like Mindflayers but with dicks instead of tentacles.

Penis Lycanthropes. Normal looking people that turned into giant dicks and attempt to screw you over.

Cum elementals
Santorum elementals
Lubricant elementals

>What kind of encounters might occur during a journey down an underground river?
Drowning, panic attacks, dead ends, starvation

>at the end of it there are three shacks
>the shacks look like they are from the nearest village
>in the left one is a dogbowl
>whoever drinks from the bowl will become the leader of the village, and it will become the most succesful place in the area
>nobody wants to drink from the bowl, and nobody wants to force anyone
>in the right one is a blank paper
>if you read it out loud you will get answers to every question you ever had
>the middle one is completely empty, but whoever is inside will hear their own breathing, even when they are not

So you mean to say exactlyExpanding on the cave kobold idea.

the kobolds are starving themselves by over fishing the cave to feed their fishy dragon master and have been attempting to breed themselves into being more aquatic.

t