When the people of Uruk suffered under the tyranny of Gilgamesh, they sought help of the gods. In response, the goddess Aururu created Enkidu as companion for the young King. To make sure that he could match Gilgamesh’ spirit, she made him two-third beast and one-third man. He would live in the wilderness for the first years of his life.
After his introduction to civilization, Enkidu became the best friend (and later brother through adoption) of Gilgamesh. Together, the two would accomplish many heroic feats; the most famous ones being the slaying of Humbaba and the Bull of Heaven.
Although these feats brought him fame, they also brought him an early death. After insulting the goddess Inanna by throwing a leg of the Bull of Heaven at her, the Annunaki decided that his time on Earth had come to an end. They killed him swiftly by sending a severe illness.