Na-Krul (Diablo I)
Na-Krul was a demon that was imprisoned by Diablo himself. He is the boss of the expansion of Diablo, Hellfire, made by Sierra. This creature was one who served as Diablo's chief minion and strongest ally, but soon Na-Krul and his cohorts were banished to the Nether Realms when he incited rebellion among Diablo's minions. Freed by an evil sorcerer, Na-Krul then set up command in the ancient Demon Crypts and once again marshalled his plans to destroy Diablo and rule the Burning Hells for himself. Gathering together a small army of never-before-seen monsters, Na-Krul possessed a threat nearly as deadly as the mighty Diablo. The player then traveled deep into the Demon Crypts and released him from his prison within his ritual chamber. Battle ensued, in which the player was able to defeat the demon.
Before the battle with Na-Krul ensues, he will say this: "Ha, ha, ha...Free! Ha, ha, ha...Free to confront the one who banished me to the void, Diablo! And free to reward you, little mortal, with your death!" It is revealed that before the fight, if the player enters a certain Command.txt exploit, he/she will hear the dreaded demon say this: "Hi! I'm free, free to confront the little man who banished me, Diablo. Hi, everybody, and I'm free to reward you, little mortal, with these Aerosmith tickets. You'll be getting backstage passes, you'll get to meet Steven Tyler and the whole band. This Friday at the Coliseum. Thanks for getting me out of there. By the way, I'm gonna have to kill you. (pause) I'll be right back with the traffic and weather together."