The World of Warcraft is an expansive universe. You're playing the game, you're fighting the bosses, you know the how -- but do you know the why? Each week, Matthew Rossi and Anne Stickney make sure you Know Your Lore by covering the history of the story behind World of Warcraft.
So the other day on Twitter someone asked me "Why were we in Karazhan, anyway" and since it's a question I've been asked before, I thought I'd address it. The primary reason we went to Karazhan was to kill a whole lot of guilds that were trying to transition to 25 man raiding from the 40 man of Classic by forcing them to run a 10 man instance and two 25 man instances at the same time. Ha. I kid, because I'm still bitter.
The question can actually be answered in several ways. We went to Karazhan because the Kirin Tor were investigating the tower and asked Khadgar for help. They had noticed that, decades after Medivh's death, some new malevolent force was infesting the tower (and since it sits on a ley line nexus, that concerned them) and as we investigated we discover the horrible truth. The Burning Legion has infested Karazhan and seeks control over the powerful arcane secrets held within, and they must be stopped.
But why did Prince Malchezaar lead his Legion forces to Karazhan in the first place? Well, for that, we have to talk about Medivh.
Medivh was the last and most famous resident of Karazhan, but he didn't build it. Indeed, no one knows who built it, or why - there's a powerful ley line nexus underneath the tower, but it's not clear if that nexus had anything to do with why the tower was originally built although it certainly seems likely. What is known is that at one point, an enormous explosion helped create the area we today know as Deadwind Pass, and following that explosion Karazhan was erected. Medvih himself maintained that the tower was built because he would eventually reside there, that its cause was his eventual arrival. We have no way of knowing if he was simply telling Khadgar the truth or playing an elaborate trick on his student. But we do know that Karazhan had strange properties - so close to the ley line nexus, time and space within the tower seemed mutable, often twisted out of what we would perceive as normal.
This is important to answer the question of why we, the players, took a trip to the place. Yes, it's because the Kirin Tor sent the Violet Eye mages to the place, but why they sent them is because of Karazhan's history. As the former home of Medivh, the last guardian of Tirisfal, the tower was renowned for its strange properties, visions of the past and future and other obscure phenomena. Moroes, the Castellan of the tower, worse horse blinders to help avoid seeing any of these visions in his peripheral vision after having seen himself in one and, despite having attempted to avoid the outcome, experience it coming to pass. While he lived there, Medivh went so far as to repulse an attempt by Arcanagos of the Blue Dragonflight, using his own essence (corrupted at that time by the presence of the Titan Sargeras) to set the dragon on fire from within. Karazhan is also the location from which Medivh plotted with Gul'dan to bring the Horde to Azeroth, and where he died at the hands of his apprentice Khadgar and his former friend Anduin Lothar. As far as the Violet Eye could later determine, upon Medivh's death and Sargeras' banishment into the Twisted Nether, a curse fell upon the tower. Those that ventured inside did not return.
However, even before opening the Dark Portal, far before the influence of Sargeras had fully manifested, Medivh had consorted with demons in his desire to learn more magic and grow ever more powerful, more knowledgeable. His experiments ranged time and space, from the Maiden of Virtue (a Titan construct) trapped within his guest chambers to the Celestial Watch, complete with a telescopic observatory, where Netherspite would prowl. It was his dabbling with demonic forces that led him to discover Gul'dan, but it was also that dabbling that most likely set up the ultimate invasion of Karazhan proper by the Burning Legion's Prince Malchezaar. What do we know about the Prince? Not a lot. We know he claims to be a Prince of the Eredar, but how he got that title and whether it means any more than a sop to his vanity is unknown. He clearly is an eredar, and when engaged in the strange spacial pocket atop the tower that seems to extend into the twisted nether itself, he boasts of the legions he commands. These legions appear to take the form of infernals that rain down upon his enemies, blasting the area with hellfire. Clearly, Malchezaar was interested in relics from all over Azeroth and some have argued that his possession of the Sunfury Bow of the Phoenix implies that he was the go-between for Kael'thas and Kil'jaeden when they forged their initial alliance. This indicates the possibility that Malchezaar was in Karazhan to use the ley line nexus as a means to bring Kil'jaeden through.
This becomes even more plausible when we consider the title 'Prince of the Eredar'. You see, unlike the other demons of the Legion, we know the eredar were once mortal. If you play a draenei, you are playing a member of the exact same race as the eredar. In fact, you are an eredar because the word eredar is the name for the original race before the coming of Sargeras to corrupt them over 25,000 years ago. At that time, the eredar race was ruled by a triumvirate consisting of Kil'jaeden, Archimonde and Velen, and of the three triumvirs only Velen rejected Sargeras' offer. The other two led the majority of their race into servitude to Sargeras, earning the name Man'ari among their people who refused the yoke. This means that the eredar of the Legion could, in fact, have children, since we see the draenei do. Among mortals the title Prince usually comes by descent, and it's possible that Malchezaar names himself thus because he is, in fact, the son of an important eredar. Now, two eredar come to mind as potential sires important enough that Malchezaar could get away with calling himself a prince, and of those two one would certainly be Kil'jaeden.
It's also possible, however, that Malchezaar simply decided to call himself Prince, and was magically potent enough to back up his claim. Either way, his presence in Karazhan was extremely dangerous, not just because there was power enough there to potentially bring Kil'jaeden through. A far worse danger existed in Karazhan, because while Medivh walked its halls, so did Sargeras. And with the time-torn nature of the tower, the past can (at least in theory) reach forward into the future. If the explosion that created Deadwind Pass happened because in the future Medivh would reside in Karazhan, and the area needed to be prepared for him, why couldn't Malchezaar learn to reach back and alert Sargeras of the ultimate failure of his plan in time for him to alter it?
Malchezaar hints at this several times, especially when he says "Time is the fire in which you'll burn" and "All realities, all dimensions are open to me." Clearly he seeks to use the tower to do exactly that, and open our dimension using time itself as the source of his power - the altered time, the celestial forces trapped within the tower.
The mere possibility that the Legion could learn how to make use of Karazhan to alter the past means that in the end, the most important raid in The Burning Crusade might have been the first one. As important as it was to stop Kil'jaeden from coming through the Sunwell, preventing the Legion from finding a way to reach Sargeras in the past was even more important.
While you don't need to have played the previous Warcraft games to enjoy World of Warcraft, a little history goes a long way toward making the game a lot more fun. Dig into even more of the lore and history behind the World of Warcraft in WoW Insider's Guide to Warcraft Lore.