A character in the online comic strip Goats by Jonathan Rosenberg. According to the bios section at goats.com, Diablo was born 20 May, 1997, is a satanist by occupation (Diablo has also mentioned that he is Satan's nephew on occasion) and is interested in "the decimation of all men's souls, brainwashing techniques, black magick, keg parties, gardening, macrame." Diablo is a talking chicken and occasionally tells rediculous tales of past exploits and gets decapitated.
One of the best things he has ever said was that "manipulation is its own reward."
A highly successful game from Blizzard Entertainment. In Diablo you played either a warrior, rogue, or sorcerer who has journeyed to the town of Tristram for whatever reason you want (money, adventure, obsessive compulsive desire to beat the unliving crap out of undead, etc.) to fight back an invading demonic horde from beneath the town, led by the strongest of the Three Prime Evils, Diablo.
As the story goes, Diablo and his two brothers, Baal and Mephisto, commanded the legions of Hell against the forces of Heaven. Unlike the Christian concepts of Heaven and Hell, in the Diablo gameworld, Heaven's inhabitants (angels) weren't necessarily good, just of the belief that order is good and chaos is bad. Hell's inhabitants (demons) believed and revelled in chaos. The two forces were constantly at war with one another, neither side having dominance over the other for long. When the realm in which humans (who could decide whether to embrace order, chaos, or a combination of the two for themselves) was found (the mortal plane), the two warring forces both attempted to gain the favour of humanity, hoping it would bring an end to the war. While this was happening, four powerful demons within Hell overthrew the Three Prime Evils, banishing them to the mortal plane. The Three went about wreaking havoc until the Horadrim, an order of magi working with the forces of Heaven, managed to capture each within a soulstone. The soulstones were separated and buried, guarded by the Horadrim for ages until differing ideas led to the eventual collapse of the order.
Flash years ahead to the town of Tristram, far beneath which Diablo's soulstone is buried: King Leoric, ruler of Khandaras, made his court at Tristram and his advizier, Lazarus, accidentally awakened and was corrupted by Diablo. Diablo sought a body to inhabit (by placing the soulstone within it) and attempted to corrupt the king as well. He was unable to fully corrupt the king but found his son much easier to take control of. After his mental battle with Diablo and the disappearance of his son, the king went insane and was eventually slain by his own guards. Since then, demons have been terrorising Tristram.
Playing Diablo is simple. To do something, the player clicks something with the mouse. Most things (talking, fighting, opening chests and doors, moving) could be done by clicking on what was to be acted upon with the mouse. Diablo brought RPG elements such as gaining levels, spells, and a variety of medieval weapons to a simple hack'n'slash action game. There are sixteen floors to the dungeons and caves beneath Tristram, which get tougher as the player descends within. What few people remain in the town above serve as sources of information, side quests, and equipment.
The game's rather addictive, especially since it could be played online for free via Blizzard's battle.net servers. Unfortunately, battle.net became far too populated with people trying to exploit the game through hack programmes and ruin it for others for battle.net to be safely played with legitimate characters and equipment. Blizzard continued releasing patches for the game and hackers kept finding new ways around the patches. A multiplayer game could hold up to four players at once either via battle.net, an IPX/SPX network, or via TCP/IP.
Aside from trying out the different character classes, Diablo was made even more replayable thanks to a random design being chosen for each level of the dungeon each time a new game is loaded. Unfortuantely, as the game is quite simple to play regardless of level design and character class, its level of replayability isn't as high as it might sound. Whether you're a warrior, rogue, or sorcerer, when all you have to do is click and run, it's not too different being one or the other. Diablo II, despite having more classes to choose from, suffers from the same problem. When the sequel originally came out, I didn't have much interest in it for quite a while due to having played Diablo too much too recently.