Sea Spider

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.

Sea Spider CR 11

XP 12,800
NE Huge magical beast (aquatic)
Init +7; Senses darkvision 60 ft., low-light vision; Perception +15


AC 24, touch 11, flat-footed 21 (+3 Dex, +13 natural, -2 size)
hp 142 (15d10+60)
Fort +15, Ref +12, Will +6


Speed swim 90 ft.
Melee bite +19 (2d6+5 plus 1d4 acid plus grab), 4 slams +18 (1d8+5)
Space 15 ft.; Reach 10 ft.
Special Attacks swallow whole (1d8+5 plus 1d8 acid damage, AC 16, 14 hp)


Str 20, Dex 16, Con 18, Int 6, Wis 12, Cha 11
Base Atk +15; CMB +22 (+26 grapple); CMD 35 (47 vs. trip)
Feats Cleave, Combat Reflexes, Great Fortitude, Improved Initiative, Power Attack, Skill Focus (Perception), Skill Focus (Stealth), Weapon Focus (bite)
Skills Perception +15, Stealth +6 (+14 when floating on the surface), Swim +18; Racial Modifiers +8 Stealth when floating on the surface
Languages Aquan


Environment any aquatic
Organization solitary
Treasure none

The hairs on a sea spider’s legs trap air bubbles, which aid in floatation and mobility. With its long, strong legs a sea spider can propel itself underwater as easily as it can glide upon the surface. Sea spiders make their lairs in shallow underwater caverns in secluded lagoons of uninhabited islands. They never leave the sea as they cannot long stand the stillness of dry land.

Sea spiders survive on a diet of plants, coral, and undersea denizens, preferring shark and eel to other aquatic life. A meal is devoured immediately, though not necessarily digested immediately. A sea spider has an extra stomach in which it stores food for later digestion. This allows the spider to go long periods of time between meals.

A sea spider is about 16 feet long and resembles a monstrous spider with fur of varying hues of blues and greens.

Sea spiders never venture on land, confining their attacks to ships. They usually attach themselves to the ship with the sticky hairs of their hind legs. This brings their mouth to the level of the deck where they may bite the ship, trying to disable it, or any person in close range. Their forelegs are free to swing at opponents. If no one is in range, the sea spider relocates to another area of the ship and attack again. Their primary tactic is to grapple opponents and draw them to the mouth, attempting to swallow them whole.


Pelagos Sea Spider

Section 15: Copyright Notice

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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