Sea urchin
Sea urchins or urchins () are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to . Their tests (hard shells) are round and spiny, typically from across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.
Urchin (Dungeons &amp; Dragons)
The urchins constitute a family of marine creatures which resemble 3-foot diameter balls of various colors with thousands of radiating 3-inch long spines. An urchin fires its spines at opponents, causing damage. An urchin is usually found in a saltwater habitat, but an urchin has a rolling locomotion on land and is capable of moving at high speed by this means. A dead urchin can be broken up quite easily, and its body contains a gem that varies in value and color according to the type of urchin.