Jellyfish, Monstrous

An enormous jelly-like being floats peacefully in the warm waters, trailing long seaweed-like tendrils from its central mass.

Monstrous Jellyfish CR 2

XP 600
N Large vermin
Init +1; Senses watersense 60 ft; Perception +0


AC 12, touch 10, flat-footed 11 (+1 Dex, +2 natural, -1 size)
hp 13 (3d8)
Fort +3, Ref +2, Will +1
Defensive Abilities jet, transparent; Immune vermin traits


Speed swim 10 ft.
Melee tentacles +3 (1d6 plus poison and grab)
Space 10 ft.; Reach 10 ft.


Str 11, Dex 12, Con 10, Int –, Wis 10, Cha 2
Base Atk +2; CMB +3 (+7 to grapple); CMD 14 (can’t be tripped)
Feats Weapon FinesseB
Skills Stealth +5, Swim +8; Racial Modifiers +8 Stealth


Jet (Ex)

A monstrous jellyfish can jet backward once per round as a full-round action at a speed equal to four times its swim speed. It must move in a straight line, but does not provoke attacks of opportunity while jetting.

Poison (Ex)

Tentacle–injury; save DC 13; frequency 1/ minute for 6 minutes; effect 1d6 Dexterity damage; cure 2 consecutive saves. The save DC is Constitution-based and includes a +2 bonus.

Transparent (Ex)

A monstrous jellyfish is nearly invisible floating in the water. An observer must succeed on a DC 20 Perception check to notice the jellyfish.

Watersense (Ex)

Monstrous jellyfish can automatically sense the location of anything within 60 feet that is in contact with water.


Environment temperate and warm aquatic
Organization solitary, pack (2-5), cluster (6-11), or swarm (12-23)
Treasure none

The jellyfish’s body is a translucent pink, blue, or purple hollow form resembling an inverted umbrella of sorts. A giant jellyfish’s body averages 8 feet or more in diameter, while its tentacles (trailing beneath it underwater) can reach lengths of around 50 feet or greater. Special muscles on the underside of the jellyfish’s body push water out of it, allowing the creature to swim through propulsion. Jellyfish eat anything that contacts their tentacles – usually crustaceans, fish, algae, and plankton. A monstrous jellyfish spends its time floating in the oceans and seas. When something contacts its tentacles, it quickly rolls its tentacles around the creature or object, attempting to paralyze and devour it.

Section 15: Copyright Notice

Monstrous Jellyfish from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Author Scott Greene

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