Crab, Bone

A cracked skull arises from the skeletal heap, scurrying forward on the bone-white legs of a large crustacean that makes the discarded cranium its home.

Bone Crab
CR 2

XP 600
N Small vermin (aquatic)
Init +6; Senses darkvision 60 ft., hive mind; Perception +2


AC 18, touch 13, flat-footed 16 (+2 Dex, +5 natural, +1 size)
hp 19 (3d8+6)
Fort +5, Ref +3, Will +2
DR 5/bludgeoning


Speed 20 ft., swim 10 ft.
Melee 2 claws +4 (1d4 plus disease)
Special Attacks disease, leap (2 claws +4, 1d4)


Str 10, Dex 14, Con 14, Int 1, Wis 12, Cha 4
Base Atk +2; CMB +1; CMD 13 (29 vs. trip)
Feats Improved Initiative, Weapon Focus (claw)
Skills Perception +2, Stealth +8 (+16 among bones), Swim +11; Racial Modifiers +8 Stealth (among bones), +8 Swim


Disease (Ex)

White ghost shivers—injury, ingested; save Fort DC 13; onset 1d3 days; frequency 1/day; effect 1d3 Con damage and 1d3 Wis damage; cure 2 consecutive saves.

Leap (Ex)

Bone crabs have incredibly powerful legs and can leap up to 10 ft. straight ahead or backward as a move action. This counts as a charge attack.

Hive Mind (Ex)

All bone crabs within 100 ft. of one another can communicate perfectly. If one is aware of danger, they all are. If one in a particular group is not flat-footed, none of them is flatfooted. No bone crab in such a group is considered flanked unless all are.


Environment any aquatic
Organization solitary or cast (2–12)
Treasure standard

Much like an enormous hermit crab, bone crabs inhabit the salvaged skulls of large fish, humanoids, and other creatures, hiding among discarded skeletons and washed up bones along the coast. Concealing their body within its salvaged bone covering, their spiny, ivory-white legs blend in perfectly with the surrounding detritus. Less-fortunate members of the species sometimes gnaw cavities into chunks of driftwood or coral in the absence of suitable skulls, regurgitating a type of lime to cement bits of shell and debris to their portable homes. Such unfortunates eagerly fight others of their kind to gain possession of choice skulls.

Voracious scavengers, bone crabs live in seaside crags and coves near coastal communities where they use their specialized chelae to crack open the skulls of washed-up bodies and feast on the decaying tissue within. Centuries of such feeding have given them a collective intelligence. Some sages have even speculated that the crabs retain fragments of memory from those they devour, by recognizing friends or relentlessly attacking foes of those whose skulls they wear.

Served by their hive mind, these crabs hunt in clever, wolf-like packs, preying on sea creatures stranded in tidal pools. Bone crabs drag such prey out above the high tide line and leave them to fester in the day’s hot sun before they feast. They pick corpses clean in a few hours, and areas infested with bone crabs are littered with cracked bone and sun-bleached skeletal remains—the perfect hiding place for these littoral predators.

Because of the bone crabs’ diet of decayed flesh, they carry a dangerous disease—white ghost shivers. As many an unfortunate and hungry sailor has discovered, this disease’s victims waste away, wracked by fever and delirium. Desperate sailors and dockside scavengers who manage to stomach a bone crab’s unwholesome, disease-riddled flesh are lucky if they live to regret it.

Although conventional wisdom claims that bone crabs cannot be domesticated, a few misguided souls have attempted to tame these diseased creatures to serve as guardian animals or companions. Never quite growing docile, the crabs have occasionally been trained to nest in particular areas, attacking intruders while ignoring the area’s regular inhabitants.

Section 15: Copyright Notice

Midgard Bestiary for Pathfinder RPG, (c) 2012 Open Design LLC; Author: Adam Daigle with Chris Harris, Michael Kortes, James MacKenzie, Rob Manning, Ben McFarland, Carlos Ovalle, Jan Rodewald, Adam Roy, Christina Stiles, James Thomas, and Mike Welham.

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