Note: My goal here was to create a comprehensive list of everything you'd need in order to learn to play any class (from Level 1 to Naxxramas)—meaning I am only including class-specific resources here (so no profession guides, general leveling guides, etc). Teeb's Resource list is much broader in scope, and I highly recommend you take advantage of it (as it contains a plethora of non-class specific resources as well). If you're not aware, Teeb is also responsible for the Race & Class Comparison Tool, Dungeon Tier Sets Gallery, and a huge variety of other insanely useful resources.
The Horde 12-20 (Barrens + Stonetalon Mountains) guide has been rewritten and revamped.  In addition, there has been numerous tweaks to the speedrun route to make things faster and easier to follow.  Also, in case you haven't noticed I am now adding about 40% more info per step and redoing all the images.  Unlike with my previous vanilla guides, I am now giving a brief explanation of where to go and what to do with each step along with any other helpful tips.
Nov 15 The most hardcore thing you can do. In vanilla? I have a few things that could be it. Playing on a perma death PvP server and kill kel'thuzad. Without dying even once. Being able to kill a mage/rogue/warlock/pally in all BiS gear Soloing a high end dungeon boss like rivendare or dark master gandling. Leveling to 60 with no gear or weapons or pet of any kind. That is by far the most hardcore, life threatening thing you can do in vanilla wowHavell7 Nov 15
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