Reader Nick writes in with a question we've been planning to tackle here at WoW Rookie for a while now: "Hey, I'm semi-new to the game, but I don't understand what a 'tier' is. My bro has a level 80 Blood Elf Hunter, and he's always saying 'Oh, he has Tier 5; I got Tier 8.' What does that mean?"
The answer to all this math is nothing more complex than the progression of class-specific armor sets. (Oh, and tell your brother he can't possibly have T8 on the live servers yet -- that's going to drop in Ulduar.) Over the course of the game, Blizzard has introduced three-, five- and eight-piece armor sets for each class. These are the so-called "Tier #" or "T#" sets that you hear so much about, all obtained by raiding. Distinguishing between the sets grew confusing as new dungeons, raids and expansions were added, so players began referring to these armor sets in numerical order.