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Pathfinder Reference Document
Pathfinder Reference Document

Parasite, Rot Grub Swarm

This nauseating carpet of wriggling white grubs undulates outward in a pallid wave of hunger.

Rot Grub Swarm CR 7

XP 3,200

N Fine vermin (swarm)

Init +2; Senses blindsense 30 ft.; Perception +0


AC 20, touch 20, flat-footed 18 (+2 Dex, +8 size)

hp 85 (10d8+40)

Fort +11, Ref +5, Will +3

Defensive Abilities swarm traits; Immune mind-affecting effects, weapon damage


Speed 10 ft.

Melee swarm (2d6 plus distraction and infestation)

Space 10 ft.; Reach 0 ft.

Special Attacks distraction (DC 19), infestation


Str 1, Dex 15, Con 18, Int —, Wis 10, Cha 1

Base Atk +7; CMB —; CMD


Environment any

Organization solitary

Treasure none

Special Abilities

Infestation (Ex) Any living creature that takes damage from a rot grub swarm becomes infested unless it succeeds at a DC 19 Reflex save. On a failed save, the infested creature takes 1d4 points of Constitution damage per round as the rot grubs burrow through and consume its flesh—this effect continues as long as the victim remains in the swarm and continues for 1d6 rounds after it leaves the swarm. Any energy-based attack (including damage from negative energy) that deals at least 5 points of damage to the victim automatically destroys all of the rot grubs infesting it, ending the effect prematurely. Additionally, any effect that removes disease instantly ends a rot grub infestation. Immunity to disease offers no defense. The save DC is Constitution-based.

Parasite, Giant Rot Grub

This twitching, pale maggot is the size of a large dog. A circular mouth quivers and gasps at one end of its pulsating body.

Giant Rot Grub CR 3

XP 800

N Small vermin

Init +1; Senses blindsense 30 ft.; Perception +0


AC 15, touch 12, flat-footed 14 (+1 Dex, +3 natural, +1 size)

hp 34 (4d8+16)

Fort +8, Ref +2, Will +1

Immune mind-affecting effects


Speed 20 ft.

Melee bite +6 (1d6+3 plus poison and grab)

Special Attacks gnaw, grab (Medium)


Str 14, Dex 12, Con 18, Int —, Wis 10, Cha 1

Base Atk +3; CMB +4 (+8 grapple); CMD 15


Environment any

Organization solitary, pair, or nest (3–8)

Treasure none

Special Abilities

Gnaw (Ex) A rot grub that is grappling a foe and chooses to damage the foe with an additional grapple check deals twice its normal bite damage (2d6+6 for most giant rot grubs), in addition to injecting an additional dose of poison with each successful check.

Poison (Ex) Bite—injury; save Fort DC 16; frequency 1/round for 5 rounds; effect 1d3 Str; cure 1 save.

Rot grubs are foul, nauseating parasites that feed on flesh and use corpses as nests in which to grow. While a rot grub can derive nourishment from dead flesh, its true hunger is for the flesh of the living. Thankfully, rot grub swarms occur only rarely, as they require the infested carcass of a Huge or larger creature and many weeks to build up the numbers necessary to constitute a swarm.

In some cases, a rot grub continues to feed and grow, eventually reaching enormous size as a giant rot grub.