This reptilian monster has eight, short legs, a short, powerful tail that ends in a pincer-like claw and a thick, barrel-like body. A large reptilian head with emerald green eyes is encircled by eight serpentine heads.

Thessalisk CR 8

XP 4,800
N Large aberration
Init +0; Senses darkvision 60 ft.; Perception +10


AC 19, touch 9, flat-footed 19 (+10 natural, –1 size)
hp 66 (7d10+28); fast healing 5
Fort +11; Ref +5; Will +5
Immune acid


Speed 40 ft.
Melee 8 serpentine bites +13 (1d8+7 plus 1d6 acid), bite +13 (1d8+7 plus 1d8 acid), tail slash +8 (1d8+3 plus grab)
Space 10 ft.; Reach 5 ft.
Special Attacks constrict (1d8+7), gaze, spit acid (40 ft. line, 4d6 acid, Reflex DC 17 half, usable 1/day)


Str 24, Dex 10, Con 19, Int 2, Wis 13, Cha 11
Base Atk +7; CMB +15 (+19 grapple); CMD 25 (37 vs. trip)
Feats Blind–Fight, Combat ReflexesB, Great Fortitude, Iron Will, Skill Focus (Perception)
Skills Perception +10, Stealth +9; Racial Modifiers +2 Perception, +4 Stealth
SQ hydra traits


Gaze (Ex)

Turn to stone permanently (as flesh to stone), range 30 feet, Fortitude DC 17 negates. A creature petrified in this matter that is then coated (not just splashed) with fresh thessalisk blood (taken from a thessalisk no more than 1 hour dead) is instantly restored to flesh. A single thessalisk contains enough blood to coat 2d3 Medium creatures in this manner. The save DC is Constitution-based.

Grab (Ex)

A thessalmonster with a tail can grab an opponent up to one size smaller with a successful tail slash attack. It can then attempt a grapple check as a free action without provoking an attack of opportunity. If it wins the grapple check, the thessalmonster establishes a hold and can constrict.

Hydra Traits (Ex)

Though a thessalmonster cannot be killed by severing all of its serpentine heads, doing so prevents them from attacking and can assist in slaying its body. Any attack that is not an attempt to sever a head affects the body, including area attacks or attacks that cause piercing or bludgeoning damage. To sever a head, an opponent must make a sunder attempt with a slashing weapon targeting a head.

A head is considered a separate weapon with hardness 0 and hit points equal to the thessalmonster’s HD. To sever a head, an opponent must inflict enough damage to reduce the head’s hit points to 0 or less. Severing a head deals damage to the thessalmonster’s body equal to the thessalmonsters’s current HD. A thessalmonster can’t attack with a severed head, but takes no other penalties.

Editor’s Note

Base template: Thessalmonster (CR +3)


Environment any
Organization solitary
Treasure incidental

A thessalisk is a cross between a basilisk and a thessalhydra. Its body grows to about 12 feet long, not including its tail, which can reach an additional length of 10 to 20 feet. The creature weighs about 800 pounds.

A thessalisk relies on its gaze attack, biting when opponents come within reach. Intruders who flee a thessalisk rather than fight can expect the monster to pursue.

Section 15: Copyright Notice

Thessalisk from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Author Scott Greene, based on original material by Gary Gygax and Wizards of the Coast.

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