Petrous CR 12

Your hands quiver as you notice the cave wall that you have been relaxing on is stirring. A hefty and hulking monstrosity with gigantic claws has taken the place of your former backrest. The beast’s gaping maw seizes hold of your arm, piercing your armor. You strain to resist and pull free! It is then that you realize your body has become paralyzed from head to toe. Bon appetit—it’s dinner time!

XP 19,200
CE Large aberration (elemental)
Init +1; Senses darkvision 60 ft., low-light vision, tremorsense 300 ft.; Perception +24


AC 23, touch 10, flat-footed 22 ( +1 Dex, +13 natural, –1 size)
hp 229 (17d8+153)
Fort +14, Ref +6, Will +13; DR 10/magic
Weaknesses light sensitivity


Speed 40 ft
Melee bite +20 (4d8+12 plus paralysis, Crit 19–20/x2), 2 claws +15 (1d8+12)
Special Attacks constrict (2d8+18), paralysis (1d4+4 rounds, DC 27 Fort), rocky grab
Space 10 ft.; Reach 10 ft.


Before Combat Petrous are incredibly patient and use their freeze special quality to hide for days or weeks at a time.

During Combat Petrous use their bites to paralyze troublesome opponents (such as spellcasters) while they claw the life from enemies that pose a martial threat.

Morale Petrous are intelligent but reticent to back down from a fight with prey, only fleeing when vastly outnumbered or when reduced to 12 hp or less.


Str 34, Dex 13, Con 29, Int 13, Wis 16, Cha 12
Base Atk +9; CMB +22; CMD 33
Feats Improved Critical (bite), Improved Initiative, Improved Natural Attack (claw), Iron Will, Skill Focus (Perception, Stealth)
Skills Climb +27, Knowledge (dungeoneering) +16, Knowledge (Geography) +13, Perception +24, Stealth +18 (+26 in stony areas); Racial Modifiers +8 Stealth in stony areas
Languages Aklo, Undercommon
SQ freeze


Rocky Grab (Ex)

When a petrous successfully hits with both claws (or rolls a natural 20 on an attack roll) it grabs its prey tightly with its claws. This initial attack deals damage normally and starts a grapple as a free action that does not provoke attacks of opportunity. The petrous has the option to conduct the grapple normally, or simply use the part of its body it used in the grab to hold the opponent. If it chooses to do the latter, it takes a –20 penalty on its CMB check to make and maintain the grapple, but does not gain the grappled condition. It then begins to crush prey using constrict. If the petrous does not constrict, each successful grapple check it makes during successive rounds automatically deals the damage indicated for the attack that established the grapple.


Environment underground
Organization solitary
Treasure double

In some of the most magically infused areas of the underworld the souls of the dead bond with the rock itself, creating a gruesome creature. Its voracious appetites never seem to cease, and whole caravans are said to have been lost to its cavernous hunger.

Petrous are 10 feet tall and nearly 7 feet across. Their incredibly dense bodies are quite heavy and some weigh in excess of 2,400 pounds.

Section 15: Copyright Notice

Aventyr Bestiary © 2017 AAW GAMES LLC Authors Mike Myler, Jonathan G. Nelson Developers, Michael Allen, Curtis Baum, Wolfgang Baur, Brian Berg, Adam Daigle, Jeffrey Gomez, Joshua Gullion, Jacob Kellogg, Jared Jeanquart, Juan Lucha, Justin Andrew Mason, Jonathan McAnulty, Michael McCarthy, Raven Mimura, Brian Wiborg Monster, Will Myers, Mike Myler, Jason Nelson, Jonathan G. Nelson, Owen K.C. Stephens, Colin Stricklin, Cory Vickruck, Stephen Yeardley Jonathan G. Nelson

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