Sea Serpent, Deep

This enormous, water-dwelling serpent has bright, bulging eyes and rounded jaws filled with long, jagged teeth.

Deep Sea Serpent CR 19

XP 204,800
N Gargantuan magical beast (aquatic)
Init +9; Senses darkvision 120 ft., low-light vision; Perception +23


AC 34, touch 12, flat-footed 28 (+5 Dex, +1 dodge, +22 natural, -4 size)
hp 333 (23d10+207)
Fort +22, Ref +20, Will +12
Defensive Abilities elusive; Immune cold; Resist fire 30


Speed 10 ft., swim 50 ft.; surge 400 ft.
Melee bite +33 (6d10+14/19-20 plus grab), tail slap +33 (6d8+14/19-20 plus grab)
Space 20 ft.; Reach 20 ft.
Special Attacks capsize, constrict (6d8+21), powerful tail, swallow whole (10d6+21 bludgeoning damage, AC 21, 33 hp)


Str 39, Dex 20, Con 28, Int 2, Wis 17, Cha 11
Base Atk +23; CMB +41 (+45 grapple); CMD 57 (can’t be tripped)
Feats Critical Focus, Dodge, Improved Critical (bite), Improved Critical (tail slap), Improved Initiative, Improved Iron Will, Improved Vital Strike, Iron Will, Lightning Reflexes, Power Attack, Skill Focus (Perception), Vital Strike
Skills Perception +23, Stealth +8, Swim +22


Elusive (Ex)

As a full-round action while in water, a deep sea serpent can move up to its run speed (200 feet) without leaving any trace of its passing (identical in effect to pass without trace). An elusive deep sea serpent gains a +40 circumstance bonus on its Stealth check. In addition, except when in combat, a sea serpent is considered to be under the effects of a nondetection spell. Both of these effects function at caster level 20th and cannot be dispelled.

Powerful Tail (Ex)

A deep sea serpent’s tail slap is always a primary attack. When a deep sea serpent deals damage to an object with its tail slap or via constrict damage, it ignores the first 10 points of hardness that object possesses.

Surge (Ex)

A deep sea serpent can surge forward as a full-round action at a speed of 400 feet. It must move in a straight line, but does not provoke attacks of opportunity while surging.


Environment any oceans
Organization solitary
Treasure triple

An enormous monstrosity that makes its home in the darkest depths of the ocean’s trenches, the deep sea serpent is as elusive as it is terrifying, the nightmare of sailors making their ways over the vast and seemingly bottomless waters. A deep sea serpent is rarely seen unless it wishes to be seen, and the beast usually has its own mysterious reasons for occasionally coming to the surface. At other times, those reasons are gruesomely obvious—the deep sea serpent rises to the surface to crush ships and devour sailors who tumble from the freshly shattered hulls.

It is thought that in incredibly remote parts of the underwater world, even more powerful deep sea serpents exist, beasts with supernatural luminous lures that can be used to blind foes, or with the ability to create overwhelming blasts of electricity that stun or even outright slay prey with a single stroke. Yet perhaps the most unnerving are the rumors of deep sea serpents that possess a remarkable intelligence. Such creatures, if they even exist, are rarely if ever seen near the surface—both their naturally elusive natures and the remote reality of their habitats mean that ensuring the veracity of these claims requires truly extraordinary efforts.

A typical deep sea serpent measures 50 feet long and weighs 35,000 pounds.

Section 15: Copyright Notice

Pathfinder Roleplaying Game Bestiary 3, © 2011, Paizo Publishing, LLC; Authors Jesse Benner, Jason Bulmahn, Adam Daigle, James Jacobs, Michael Kenway, Rob McCreary, Patrick Renie, Chris Sims, F. Wesley Schneider, James L. Sutter, and Russ Taylor, based on material by Jonathan Tweet, Monte Cook, and Skip Williams.

scroll to top