Run Azar is invented by Veskin7 Bukito.
Run Azar is a powerful demon that is meant to be the leader of Diablo's army.
He is a leader of a fearsome demon army called Nightmares. The Nightmare demons use elemental forces like Fire, Ice, Lightning and Poison. Actually each demon possesses one of the element powers. There are Fire Nightmares and Poison Nightmares that are often met, and Ice and Lightning Nightmares that are rare.
The story tells that Run Azar and his army served Diablo since he first walked the earth. The army of Nightmares leaded by Run Azar fought Tyrael, but the clever archangel lured them into a trap and used powerful holy force to imprison them. This was a great loss for Diablo himself.
When the fiery harbinger of doom /the meteor/ fell on the ground its powerful magic destroyed the prison of the Nightmares and Run Azar, and they were finally free.
Feel free to edit this picture or make your own version of Run Azar.