Set between the events of Diablo II: Lord of Destruction and Diablo III , the story follows the aftermath of the destruction of the .
You can get the official PC version directly from the developer:
Skarn, the Herald of Terror and Diablo’s most powerful lieutenant, seeks these fragments to resurrect his master and start a new demonic invasion.
You play as a hero tasked with gathering these fragments before the Burning Hells can use them to enslave humanity. How to Download Safely (Free)