These humanoids have a thick, warty skin, webbed extremities ending in claws, and bulbous eyes that have a feral gleam. A row of needle-sharp teeth poke from their frog-like mouth and spines cover their backs. These creatures were once murlocs, but were mutated by the Sundering. The Mur’Gul delight in capturing both humans and murloc, torturing and then eating their victims. They infest the sea, clambering aboard vessels and slaying everyone onboard.
Mur’Gul are distinct from mutant murlocs, having originated earlier and being significantly stronger. These beings form small groups, often but not always related. Such gangs steal from one another, and Mur’Gul will try to raid nests of rivals for eggs to eat. Mur’Gul organize in a rather spontaneous way, primarily to raid murlocs or humans. If these raids go poorly, the Mur’Gul may very well turn on one another.
Mur’Gul wander, and many do not even have a fixed territory; lairs are temporary affairs, used to hold prisoners or for mating. They only keep equipment they can either use or carry easily, though a temporary lair may have treasures from past victims. These savage creatures fear only one race: Queen Azshara's Naga of Nazjatar. Despite their own vicious nature, Mur’Gul are superstitious and fear the magical power of the Naga, who have enslaved numbers of Mur'guls and use them as cannon fodder and labor force.