Diablo is an ARPG game based in a dark fantasy setting developed by Blizzard North and released by Blizzard Entertainment on 30 November, 1996 in North America (2 January 1997 in PAL territories).
The game is set in the fictional world of Sanctuary, centred around the town of Tristram in the Kingdom of Khanduras. The protagonist is a lone hero who takes upon himself to find what is causing distress in the town's cathedral and is taken upon a journey that brings him down into the deep caves beneath the cathedral, all the way into Hell to combat Diablo, the Lord of Terror.
An official expansion pack, entitled Diablo: Hellfire, was released in 24 November 1997 (1998 in PAL territories) by Sierra On-Line (developed by Synergistic Software). However, because it was not created by Blizzard Entertainment, the entire game is considered to be retconned out from the lore of the game world.