Diablo is Blizzard North's original action RPG, released for PC (DOS/Windows) on December 31, 1996. This entry covers the original PC release only. It introduced the dungeon-crawling formula and randomized loot systems that became foundational to the genre.
Expansions & DLC
Hellfire (1997)
An unofficial expansion developed by Synergistic Software and published by Sierra On-Line (not Blizzard), adding a new act, the Monk class, and additional dungeons and items.