Aghul

A deadly monster from the depths of the swamps of Bah Jubal or Campanga Quagmire. It's habitat is any place with plenty of water. He squirts noxious saliva, comprising complex mixtures of various venoms, at his victims. In ancient times, when humans were slaves to dwarfs, it was a venerated deity, who received an annual sacrifice of a dozen humans. That led to the famous human mutiny that a hundred unsuccessful years later, escalated into a revolution and resulted in the liberation of human kind.

Subspecies

 * Aghul
 * Venom aghul
 * Great aghul

Source

 * Official site