Surfacing from the depths emerges a colossal slug. Its swollen flesh is a hideous mottled greenish-gray and rows of undulating gills line its 30- foot long body. Probing with a large set of antennae it gnashes its great mouth exposing a gullet lined with rows and rows of serrated teeth.
Giant Sea Slug CR 12
XP 19,200
N Gargantuan vermin (aquatic)
Init +0 Senses darkvision 60 ft.; Perception +6
Environment temperate aquatic
Organization solitary
Treasure none
Spending a large portion of its life crawling across the floors of lakes and seas, the giant sea slug is rarely encountered, save by accident or happenstance. Stories are told of these great monsters surfacing beneath ships, tipping them over, and then feasting on the survivors. There is little truth to these stories, as the giant sea slug prefers a diet of plants and aquatic sea life. Instead, giant sea slugs are docile creatures, dieting on aquatic plants such as kelp, seaweed, and coral. They are known to surface for air occasionally though they do not require air to breathe. Most of the stories that speak of these creatures attacking ships are the result of a giant sea slug surfacing for air beneath a ship that happened to be in the way.
A typical encounter with a giant sea slug occurs when the creature surfaces beneath a ship or boat and capsizes it. The giant sea slug isn’t really attacking, it’s just surfacing for air – and once again a ship or boat has gotten in its way. They may inadvertently swallow sailors or swimmers who are in the water when the giant sea slug opens its mouth. Non-aggressive, they rarely engage in combat, however if provoked, they attack opponents by biting with their sharp, jagged teeth.
Giant Sea Slug from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Author Scott Greene.