Narantaka (Narāntaka) (or Narantak) and Devanataka (Devāntaka) are Asuras (demon) who appear in a number of Hindu legends.
Story
In the Ganesha Purana, they were a son of the rishi Rudraketu. In Satya Yuga, after praying to the god Shiva, they were granted boons and become powerful and cruel rulers. They assume sovereignty over svarga. In response Ganesha, a popular elephant-headed god in Hinduism, turns into an avatar named Mahotkata. He battles the Demon army with help of the Ashta Siddhi. Eventually, Mahotkata manages to kill Devantaka with one of his tusks.
In the epic Ramayan (which happened in Treta Yuga), they are the rakshas (demon) sons of the evil demon king Ravana. Narantaka was in charge of an army consisting of seventy-two score (720 million) rakshas. He with his army was eventually killed by the vanara Hanuman. Devantaka is killed by Angada during a war.