Kos'Karii
In Klingon mythology, the Kos'Karii were pale, serpent-like creatures which inhabited the blood-red waters crossed by the Barge of the Dead on its way to Gre'thor. They attempted to lure dishonored souls to them with voices of friends and loved ones, and then drag them into the water. 

In 2376, while experiencing a ride on this barge, B'Elanna Torres was told by Hij'qa that the voices she heard were not her crewmates on , but the Kos'Karii. Later, Miral mistook her own daughter for one. ()

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Qo'noS
Animals
Mythological figures
Klingonese