So a few days after The Burning Crusade came out we went through all the new end-game content in an effort to prepare ourselves and our guildies for the upcoming attunement grind. We knew it would be hard, having experienced endless Jailbreaks and UBRS runs, but we didn't expect that we would have sit down and create a flow chart of the instances in order to even begin to comprehend the convoluted, overlapping, intricate Rubik’s Cube of pre-quests, key chains and attunement runs.
So after we did all that work, we decided it wasn't doing anyone any good buried in our computer somewhere, and decided to share. So here you go: the basic steps every player needs to follow in order to get attuned.
Nope, the first instance you should run in order to be prepared is at level 65+, Sethekk Halls in Auchindon, Terokkar Forest. The last boss drops the key to the Shadow Labyrinth, which comes into play later. It can be hard at 65, but can be done.