This transparent jellyfish-like being occasionally flickers with a weird green inner light that steadily flashes on and off.
Marsh Jelly CR 3
Speed 5 ft., fly 30 ft. (average)
Melee 4 tentacles +6 (1d6+3 plus poison)
Special Attacks death throes, disorienting glow
Str 16, Dex 13, Con 15, Int 3, Wis 12, Cha 10
Base Atk +3; CMB +6; CMD 17 (can’t be tripped)
Feats Improved Initiative, Skill Focus (Perception), Stealthy
Skills Escape Artist +3, Fly +5, Perception +10, Stealth +7
When slain, a marsh jelly explodes in a blast of acid that deals 2d6 points of acid damage to anything within 10 feet. A successful DC 14 Reflex save reduces the damage by half. The save DC is Constitution-based.
When a marsh jelly first takes damage, its body begins pulsating and flashing rapidly, emitting an eerie greenish glow. Creatures viewing a pulsating marsh jelly must succeed on a DC 14 Will save or be dazzled for 1d4 rounds. The save DC is Constitution-based.
Environment temperate marshes
Organization solitary or globe (2-5)
This bizarre creature floats slowly through the gloom of swamps and marshes. It has a gelatinous body reminiscent of a jellyfish that is nearly translucent, its four stringy tentacles dangling beneath it in a constant hunt for food. Marsh jellies are roughly man-sized and tend to thrive on giant swamp rats, and other creatures smaller than itself. It is not uncommon however for a marsh jelly or a globe of such creatures to prey on unwary travelers who stray to deeply into open marshland. Marsh jellies are responsible for the strange disappearance of many who enter their swamps for they digest their prey, bones and all, leaving only acidresistant precious metals such as gold behind.
A marsh jelly looks like a hovering, flying jellyfish with a translucent sickly green body and four long dangling grayish-pink tentacles. Many smaller tentacles ring its body and aid the creature in locomotion as well as detecting scents in the air. A marsh jelly’s body emits a pulsating glow when it is threatened or damaged, and the creature can likewise use this glow to lure prey closer to it.
Marsh jellies descend on their prey from above, stinging repeatedly with their venomous tentacles. When wounded, their translucent flesh begins to pulse rapidly with a flashing green strobe effect that tends to disorient its prey, and any other creatures who may seek to harm it.
Marsh Jelly from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Author Scott Greene.