In 1996 an event took place that would change the landscape of role-playing-games forever, it was the year that Blizzard Entertainment would release the very first Diablo computer-game. At the time role-playing games were not very exciting, considering that in most cases you would only direct your character to do some action, like attacking an enemy, with you just watching the fight scene.
However with Diablo, your character interacted with the world called Sanctuary. In the Kingdom of Khanduras, there is a town called Tristram, where your character gets called to. The hero you could play, was either a Warrior, a Rogue or a Wizard, but this hero came home to Tristram to find that the Church-Labyrinth at the end of the town is crawling with demons and other hellish monsters.
According to one of the Elders, Deckard Cain, the arch-bishop in the town, Lazarus had vanished after leading the towns folk on a rescue mission to find the prince of Khanduras, when the demons and hellish creatures suddenly appeared. A battle then followed where many of the towns folk were either killed, injured or lost. The hero immediately sets of to the Church-Labyrinth to look for answers and what he finds is not pretty.
Inside the Church-Labyrinth, the hero would go to battle various monsters and demons, eventually encountering the skeleton of King Leoric, buried three levels below the town. The skeleton king was as tough as they come, the big sword he yields does your hero a lot of damage, but when he gets defeated, he gives the hero his crown as a sign of gratitude for helping him rest in peace.
Now what was awesome about the first Diablo game, was that your quests and missions would be randomly generated, each time you started the game. In some cases the hero would find a dying-warrior in front of the church, who would ask the hero to find, the Butcher thereby avenging Tristram's fallen and massacred soldiers. The Butcher had a massive cleaver which would become the hero's weapon once he defeated the Butcher.
As the hero makes his way further down the labyrinth, the hero will eventually reach the Archbishop Lazarus, whom you needed to beat to get to the last boss of the game, Diablo himself. The really awesome thing with this game was that as you played your way into hell, the areas where the hero was fighting would change as well. The hero would eventually be battling Diablo in a room that has walls of flesh and doors of bone. When the hero defeats Diablo, he gets a red stone which he drives into his own head, a weird ending but it becomes clear when you play the sequel.
Nevertheless I believe that this game set a standard in 1996 that would become the foundation for the Role-Playing Game genre for years to come. This game was way ahead of its time when it came out in 1996, and is still one of the games I regularly play, because it is still playable in 2012.