Like snails and other sea slugs, the magnificent sea slug is a gastropod. Most gastropods have a hard shell outside (not the magnificent sea slug, though) and a muscular foot that they use to move around.

Though it can’t see, it has two tentacles on its head called rhinophores and two near its mouth called oral tentacles, which allow it to smell, taste, and feel its way around the reef. The feathery parts on the back of its body are gills that it uses to breathe in water.