Diablo is an action role-playing game developed by Blizzard Entertainment and released in 1996 for Windows 95 and DOS. It combines real-time combat with dungeon crawling in a dark fantasy setting. Players choose from three character classes, Warrior, Rogue, or Sorcerer, and descend through sixteen randomly generated levels beneath the town of Tristram, battling demons and the undead to confront the Lord of Terror, Diablo. The game's simple click-to-attack interface, loot-driven progression, and randomized quests made it a landmark title that popularized the action RPG genre. Its multiplayer component via Blizzard's Battle.net allowed up to four players to cooperate or compete, though peer-to-peer connectivity led to widespread cheating issues. Diablo received critical acclaim for its addictive gameplay, atmosphere, and replayability, and spawned the expansion Hellfire (1997) and the acclaimed sequel Diablo II (2000).