_A bone crab’s cracked skull scurries forward on bone-white legs. These tainted crustaceans make discarded craniums their home._ **Skull Shells.** Much like an enormous hermit crab, bone crabs inhabit the remains of large fish, humanoids, and other creatures. A bone crab’s spiny, ivory-white legs blend in perfectly with bones and pale driftwood. When lacking bones, these crabs gnaw cavities into chunks of driftwood or coral to make a shelter, cementing bits of shell and debris to their portable homes. All crabs fight over choice skulls. **Scavengers of Memory.** Bone crabs are voracious scavengers. They live in seaside crags and coves, where they use their specialized chelae to crack open skulls and feast on the brains. Centuries of such feeding have given bone crabs a collective intelligence. Some crabs retain fragments of memory from those they devour, and these crabs recognize friends or attack the foes of those whose skulls they wear. Bone crabs hunt in packs, preying on seabirds and creatures stranded in tidal pools. They drag aquatic prey above the high tide line and leave it to fester in the hot sun. They pick corpses clean in a few hours, so their hunting grounds are littered with cracked and sun-bleached bones—the perfect hiding place for these littoral predators. **White Ghost Shivers.** Because they eat carrion, bone crabs carry a dangerous disease—white ghost shivers, which wrack victims with fever and delirium. Sailors and others who eat a bone crab’s unwholesome, diseased flesh rarely survive it. Although bone crabs cannot be domesticated, they can be convinced to nest in particular areas, attacking intruders while ignoring the area’s regulars.