Clear River Jellies

I wanted to write a monster that played with the information available to PCs. So I wrote this, the Clear River Jelly.

Look at these dangerous fellows.
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The marshes of the lower river Sargal are home to carnivorous, gelatinous creatures called Clear Jellies, River Jellies, or sometimes Glass Jellies by foreigners who know what glass is. They start out tiny, just eating insects and algae, but once they grow in size they become a threat. The jellies aren't fast but they've developed a few adaptions which help them hunt. One, they're clear, even large ones can barely be seen floating down the river. Two, their bodies are full of a numbing agent which dulls the sensation of them digesting you. Fish often swim through River Jellies and don't realize they've being eaten until its too late, same thing happens to unlucky swimmers. Large river jellies are pretty brave and pretty clever. They'll wait by the river's edge to snatch prey, they'll bust holes in the hulls of boats and drag them into the water.


River Jelly
Large ooze, unaligned
Armor Class: 8
Hit points: 45 (6d10 +12)
Speed: 10ft., swim 15ft., climb 10ft.
 Str 16 (+3) Dex 6 (-2) Con 15 (+2) Int 4 (-3) Wis 6 (-2) Cha 1 (-5)
Damage Resistances: acid, fire
Condition Immunities: blinded, charmed, deafened, exaustion, frightened, prone
Senses: blindsight 60ft (blind beyond this radius)
Languages --
Challenge: 2 (450 XP)

Amorphous. The jelly can move through a space as narrow as 1 inch wide without squeezing

Invisible in Water. The jelly is invisible while fully immersed in water.

Anaesthetic body. Any creature which takes acid damage from the jelly must make a DC 13 constitution saving throw. If it fails, a feeling of numbness fill its body and it cannot tell how many hitpoints it has. This effect lasts for an hour. If a player character is effected by this trait, the DM records their HP for them. If a creature suffering from this effect takes acid damage from the jelly again, it must attempt the saving throw again. If it fails, it is paralyzed until the end of its next turn.

Actions:
Pseudopod. Melee Weapon Attack: +4 to hit, reach 5ft., one target. Hit: 9 (2d6 +2) bludgeoning damage plus 3 (1d6) acid damage.

River Jelly can be made into a potent pain killer if a pound of it is boiled for half a day and then strained through a piece of cloth. A creature who drinks the resulting clear-ish sludge may ignore one of their minor wounds and must make a DC 14 constitution saving throw. If they fail their save, the jelly is too effective and they become numb and are unable to tell how many hitpoints they have. Both of these effects last a day.

Most people who live along the river know how to properly process River Jelly and will show the PCs the procedure if they manage to catch or collect a River Jelly.

I want you to imagine aggressive ballistic jelly. Now that's good D&D.
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This post is dedicated to Hannah Glasse