Corrupting Runoff. The foul brine that perpetually spews forth from the mass of coral and shell on the Deep-kin Reef Crawler's back quickly alters its environment, turning it into a bone reef covered in coral and barnacles. The terrain changed by this run-off persists for days, even after the Deep-kin Reef Crawler is slain.   Terrain within 15ft of the Deep-kin Reef Crawler is transformed into Abyssal Reef, non Deep-kin treat this as difficult terrain and are dealt 1d4 for every 10ft of movement they spend traversing it.   Locus of Loss. The mere presence of a Deep-kin Reef Crawler instils an unexplainable sense of loss. Creatures within 150ft of the Deep-kin Reef Crawler gain a -1 penalty to all saving throws against effects attempting to Charm or Frighten them.   Spider Climb. The Deep-kin Reef Crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.