Sea Spider, Pelagos

This creature resembles similar arachnids found on land. Its color ranges through various shades of blue and green with distinct black markings. Its legs and bodies are covered with thousands of fine, sticky hairs.

Pelagos Sea Spider CR 15

XP 51,200
N Huge magical beast (aquatic)
Init +8; Senses darkvision 60 ft., low-light vision, watersense 60 ft.; Perception +31


AC 28, touch 12, flat-footed 25 (+4 Dex, +16 natural, -2 size)
hp 230 (20d10+120)
Fort +20, Ref +16, Will +12
Resist acid 10, cold 10, fire 10


Speed Swim 90 ft.
Melee bite +26 (2d8+7 plus poison plus grab), 4 slams +25 (2d6+7)
Space 15 ft.; Reach 10 ft.
Special Attacks swallow whole (2d6+7 plus 1d8 acid damage, AC 18, 23 hp)
Spell-like Abilities (CL 20th):

3/daycone of cold (DC 19), lightning bolt (DC 17) (affects a 30-ft. radius around the pelagos rather than a single target)
1/daystinking cloud (DC 17)


Str 25, Dex 16, Con 22, Int 20, Wis 18, Cha 18
Base Atk +20; CMB +29 (+33 grapple); CMD 43 (55 vs. trip)
Feats Alertness, Cleave, Combat Reflexes, Great Fortitude, Improved Initiative, Iron Will, Power Attack, Swim-by Attack, Weapon Focus (bite)
Skills Diplomacy +24, Escape Artist +24, Knowledge (nature) +25, Knowledge (religion) +25, Perception +31, Sense Motive +28, Stealth +17 (+25 when floating on the surface) , Swim +20; Racial Modifiers +8 Stealth when floating on the surface
Languages Aquan, Common, Draconic, Elven, Sylvan


Poison (Ex)

Bite—injury; save Fort DC 26; frequency 1/round for 4 rounds; effect 1d3 Con damage; cure 2 consecutive saves.

A creature that dies from this poison turns into water and flows away (and is irrevocably dead save for a miracle, wish, or the intervention of a deity). The save DC is Constitution-based.

Watersense (Ex)

A pelagos can pinpoint the location of anything within 60 feet that is touching the water.


Environment any aquatic
Organization solitary
Treasure standard

This great sea spider makes its home in the deep ocean never venturing close to the coast or shorelines. Its lair is often made in sunken ships or underwater caverns and caves. It sustains itself on a steady diet of fish and aquatic plants.

A pelagos is thought to be the creation of an ancient sea god set upon the world to either guard or harass ships and waterborne travelers. Many cultures revere the great pelagoses as sea gods themselves and often make sacrifices to them to ensure a safe ocean journey (or to bring about a curse upon the heads of pirates, buccaneers, or other water bandits who have wronged the community).

Section 15: Copyright Notice

Pelagos Sea Spider from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Authors Scott Greene.

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