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A deep sea murloc is a species of murloc that presumably lives in the ocean depths, likely in locations such as the Vashj'ir. They are blind and strongly resemble anglerfish, with sharp fangs and bioluminescent growths protruding from their foreheads. They might be related to the mur'gul.
In the Throne of the Tides dungeon these deep sea murlocs appear to be serving the naga, though it is unclear if they serve by choice or are forced to.