I'll start off by saying that while I'm going to attempt to answer what the story of vanilla WoW is, it's really a question best left to The Man himself, Chris Metzen. In fact, I'll try something: Chris, if you're reading this, we'd all love to hear your answer -- drop me your email via the tip line and we'll get in touch. Perhaps we can do an interview about this and post it for everyone.
Okay, probably a snowball's chance in hell of him actually responding, but what kind of editor would I be if I didn't try?
I think the story of vanilla WoW is three fold.
One - Passing the Torch to a New Generation
The heroes of yesteryear are passing the torch to a new generation, and represent a significant part of the story in vanilla WoW. This new generation of heroes are not represented by an NPC in the game, but by the players themselves. As a player you develop your reputation from simple tasks of clearing out wolves in the relatively peaceful Elwynn Forest to taking down Ragnaros and defeating the old god C'Thun. This sets the stage for future stories where the heroes, the protagonists of the story, are more developed -- namely the overall story arcs of the Sunwell, Illidan, and Kil'jaeden from the ancient war in Burning Crusade, and the battle with Arthas in Wrath. I'll note here that Arthas has a definitive presence in vanilla WoW even now out in the Plague Lands, and even more so prior to Naxx's removal; but the real story with Arthas ends in patch 3.3 (we think).
Two - The Nation-State Reconstruction
Another story of vanilla WoW is about the consequences of the reconstruction of Azeroth from the third war. Approximately 4 years have gone by since Arthas and his scourage forever changed the face of the planet. We've seen old allies fall into strained relationships, and have seen new friends spring up from the most conflicting of groups. These varying relationships have led to nation-state interaction that propels the heroes (the players) into epic battles between factions like the Horde and the Alliance, and between the Dark Iron Dwarves and Bronzebeard's forces.
And while the aftermath of the third war and the subsequent reconstruction provides a great bed upon which to weave epic tales, the actual reconstruction and the eternal human spirit play a central role as well. Azeroth was devastated after Arthas. Land which was once green and fertile became gray and dead; creatures of the world found themselves corrupted by the evil force of the Lich King, and entire civilizations found themselves turned upside down with an attack directly on their capital (Lordaeron and Silvermoon)*.
In this way the compelling story of the successful yet difficult reconstruction is one that is able to connect with WoW's audience directly in their sense of nationalism (belonging to a nation), and of dealing with our world which was directly changed after the terrorists attacks of 9-11. No matter where you're from or what your particular political and social philosophy is, the 9-11 attacks somehow changed the way of life of your country. For Americans in particular, and indeed for any peoples which had to go through terrorism, there is a strong sense of having to deal constructively with these difficult situations. We must rebuild, we must make sure this doesn't happen again, we must never forget. Such are universal slogans in the fight against evil. Azeroth must rebuild, enemy and ally alike. Azeroth must make sure the Lich King is never able to wrought his kind of destruction again. Azeroth must not forget what he did, lest the Lich King is able to snake his way back into power over the peoples of the entire world.
This story and the feelings it presents reverberate deep within the primary audience which plays WoW now -- the 20 to 30 year olds who were young adults when the attacks and subsequent global terroristic outbreaks entered into our global consciousness. In many ways Azeroth represents a return to normalcy and strength. Concepts that, while we might not identify directly with it ourselves, we can at least identify with it on a nationalistic level.
And here too we reach the finality of such a reconstruction -- the ultimate triumph of good over evil. The Third War was evil. We outside the game will triumph over evil, just as our characters do in the game. At a very basic level this story is perhaps the most compelling out of all stories from all expansions -- and as detailed above, fits into the psyche of people so well today that it's uncanny.
Three - New and Emerging Threats
The Lich King, the Horde, the old gods -- all of those are old threats. The ancient war dealt with the great sundering and Queen Azshara, the first war dealt with initial conflict between the Horde and the Alliance as the Horde entered through the Dark Portal from Draenor. The second war saw continued conflict between the Horde and the Alliance. And finally in the third war we saw the Lich King assert his presence in the land. They are all very astounding tales of dramatic movement on both the individual level and national level, however they all represent relatively old threats.
In vanilla WoW, new threats emerge. While many of these new threats are the reemergence of old creatures like Ragnaros or C'Thun, they feel like the modern time is the right time for them to rise from the depths and become victorious over the people of Azeroth.
"Too soon, you have awakened me too soon, Executus!"
Even though Ragnaros is planning on taking over Azeroth, starting with making life from stone in Blackrock Mountain, he knows he's not yet made the necessary preparations. As new heroes of the land we have to go and stop this elemental lord of the age of the Titans, to stop this new threat from returning us to the evil that we saw during the Lich King.
This story can be repeated, more or less, for the events of AQ and ZG. Stop old gods (not the old gods, well, not always) from coming back into the evil-power-vacuum left by the Lich King.
The story of vanilla WoW is not as clear cut as BC or WotLK. It does however still provide amazing plots and adventures that hearken back to the very nature of an MMORPG; you face a world in which you have to fight against evil, struggling to win a battle that can never be won. The forces of the Lich King might be banished to fester in the cold north, but in his place other denizens of the underworld creep up and try to take his place. In an MMORPG, you are left forever defending your freedom and way of life against forces which attempt to end it.
In many ways vanilla WoW is the most compelling story of all the iterations of WoW, because it's the story of Humanity's spirit and relentless will to live.
I must insist that all comments are kept civil. The piece is here not to debate the merits of American hegemony or the democrats vs. republicans, but the story of vanilla WoW and its connections with all of us.
*I'd be amiss if I didn't note that I debated adding a fourth major story arc -- that of environmentalism. The night elves, tauren, and orcs have very strong and compelling story lines dealing with protecting or in someway acting as the agent of the earth. And while this story line is a major part of WoW for some, it's not for all. For instance Putress representing the undead for awhile seemed pretty hellbent on poisoning everything, including the land. And while the dwarves revere the land, they also like to dig a ton of it up. And the gnomes are particularly bad with their oil dropping out in the Borean Tundra. So while the story of environmentalism is there, it's not a major part of WoW yet, and it doesn't follow an overall path yet either (those stories about being pro-earth and anti-earth are not really connected). An example of a story having an environmentalism arc would be Lord of the Rings (the book version, not the movies) or Dune; and WoW doesn't have it to that extent yet.
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