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Preview From Shore to Sea:
Bone Crabs

Preview From Shore to Sea:
Bone Crabs

I tell ya, boys, we’ve fished up and down this coast for years and never seen anything like ’em. We’d found what was left of Ol’ Patch and his crew — washed up on the shore there, all picked apart to bones and gristle. It was bad enough seeing ’em like that, and worse when crabby legs and claws popped out of the skulls and skittered toward us.

The damn critters knew what they were doin’, too. Thinkin’ on it, that’s the scariest part — they worked like wolves, and they waited for the tide to come in to trap me and my boys. Cutlasses barely hurt ’em — just bounced right off skull-shells. Hell, I was lucky I lost just three fingers…

Voracious scavengers, bone crabs live in seaside crags and coves near busy coastal communities, where they use their specialized chelae to crack open the skulls of washed-up bodies and feast on the decaying brains within. Centuries of such feeding have given the vermin an acute collective intelligence, a hive mind that serves bone crabs very well indeed.

Bone crabs inhabit the salvaged skulls of humanoids, into which they can retract their spiny legs for protection and concealment. The scavengers are specially suited to their ecological niche, and their foraging makes the crabs carriers of a dangerous disease, as many an unfortunate and hungry sailor has discovered. Those lucky enough to survive their attacks often succumb to high fever, consumption and delirium.

Bone Crab CR 2

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

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

20 ft., swim 20 ft.
Melee 2 claw +3 (1d4)
Special Attacks Disease, leap (2 claws +3, 1d4)

Str 10, Dex 14, Con 14, Int 4, Wis 12, Cha 4
Base Atk +2; CMB 0; CMD 12 (16 vs. trip)
Feats Improved Initiative, Weapon Focus (claw)
Skills Perception +2, Stealth +7, Swim +8

any aquatic
Organization solitary or pack (2–20)
Treasure none

Special Abilities
Disease (Ex)
White ghost shivers: Claw—injury, ingested; save Fort DC 12; onset 1d3 days; frequency 1/day; effect 1d3 Con damage and 1d3 Wis damage; cure 2 consecutive saves. The save DC is Constitution-based.
Leap (Ex) Bone crabs have incredibly powerful legs and can leap up to 10 feet straight ahead or backwards 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 are. No bone crab in such a group is considered flanked unless all are.
Home of Bone (Ex) When a bone crab hides in its adopted home it resembles a discarded skull. An observer must succeed with a DC 20 Perception check to notice the bone crab.

This is the first preview of the official Paizo adventure, From Shore to Sea. To see more — or to contribute your own design to the published work — become a patron of the project today.

Art by Hugo Solis
Open Game License for Bone Crabs

21 thoughts on “Preview <i>From Shore to Sea</i>:<br /> Bone Crabs”

  1. Is that normal a Vermin with an INT score of 4 ?

    I thought vermin should be mindless, and have no INT score.

    Is this monster subject to mind-affecting spells ???

    I think this monster should be a magical beast, not a vermin.

  2. BIG Thanks to Daigle for his assistance outlining this critter and kicking around ideas with me.

    MRick -the vermin type does have a concession for intelligence. It is rare, but a concession is provided.

  3. Interesting. A swarm of these would be downright scary.

    Minor nitpicks:
    – “small size” – “A character or monster is considered Small when he, she or it stands 2 to 4 feet tall while weighing 8 to 60 lb.” In other words, these crabs are pretty big and so hiding inside skulls of most creatures would be pretty hard for them to do.
    – since the introduction mentioned cutlasses (slashing). While crab’s armor rating is pretty high, should not it have DR 5/slashing?
    – Home of Bone sounds pretty nonstandard. Should not be just racial Stealth bonus for hiding among bones as it appears to be a pretty standard opposed check of Perception vs Stealth?
    – very high swimming speed. Is it feasible for crabs to swim so fast?
    – shouldn’t Hive Mind be a Supernatural ability? It’s not like telepathy is a common ability among vermin.


  4. Very cool! As an example of what happens in an Open Design Project, folks should know that these beasties arouse out of community discussions with back and forth ideas from project memebers.

    I think it shocking and provocative that vermin have weird abilities in special instances.. otherwise vermin quickly become alternate versions of the same creature. The Hive Mind ability is in an interesting and clever way to depict that ability.

  5. There is an art credit for Hugo Solis. It is, perhaps, in too small type. I suspect more of his work will appear in the Sunken Empires part of the project.

    The intro pointed out that slashing damage didn’t really work, so DR 5/bludgeoning seems correct to me.

    The Small size does seem like it might be an error, but I’ll leave Mr. Hodge to explain that choice.

  6. Well, I felt it a little unbecoming to defend my beastie after posting it, but in the interest of a good design discussion, I’ll give it a go:

    The small size call was an odd one. Pixies and ravens are tiny, but dogs and dire rats are small. This thing is the size of a king crab, and those suckers can get up to 20 pounds, so add in a skull and a pretty big leg spread and you’ve got yourself a small creature.

    You guys already know I’m weird, but I actually did a mockup at home in my living room with a chimp skull and some king crabs legs. The sucker was big and creepy.

    We later boiled the legs to celebrate the bone crab’s debut! =-)

    If anything, this explanation does call the home of bone ability into question. This is just the gargoyle’s freeze ability renamed, so it isn’t without mechanical precedent. But, the poor feller is going to have a hard time getting those big legs in that little skull. My explanation? These crabs are bone white, and they are smart enough to lie there limply and, well, they’d look like a pile of bones…

    Wolfgang already called the DR question. They live in a skull, so we gave them a skeleton’s DR!

    As for hive mind, most of the Tome of Horror examples I looked up had it listed extraordinary. In the real world, ants and molerats and even some birds have similar abilities, so why not creepy crawly fantasy crabs?

  7. Thank you for addressing my nitpicking. I’d like to apologize for making a rather inane remark about the DR – the skeleton reference is very telling.

    Maybe the Home of Bone could be a little reworded to point toward similarity of Hermit Crab habit of acquiring shells? And again, gargoyles nonwithstanding, fixed DC does not sit well since most creatures get rather racial Stealth bonuses instead.

    Regarding hive mind… according to SRD the only two creatures to have Hive Mind (Formians, Hellwasp Swarm, both listed as Ex) are of Outsider or Magical Beast type, in other words, they are anything but usual vermin. Looking at Telepathy (silent mind-to-mind communication) we have it as Supernatural for a few SRD creatures I’ve checked.

    Still, all of these are minor – please ignore my suggestions if you feel they are not justified. The reasons I raised them are:
    – building advanced versions of this creature would play nicer with relative Stealth bonus (it’s hard to imagine Huge version getting the same DC)
    – Hive Mind being supernatural would allow better fighting chance for Detect Magic users while offering a nice bad vibe to anyone spotting weird auras all over the nice and empty beach


  8. Cool critter! Nice surprise for an arrogant party: “Oh, just some little crabs….Wait what are they doing?!”

    Wasn’t there in some old Greyhawk adventure a spider that lived in a old lich’s skull, and thus had gained intelligence and magic? Does anyone have an idea which adventure that was again?-P

  9. Very cool indeed! From the writeup, these would make good crypt or catacomb dwellers. I think these just became subterranean…

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