Atal'Dazar is a dungeon whose entrance is located in Zuldazar in the World of Warcraft game. The level range for the normal dungeon is 110-120. The dungeon contains 4 bosses. The end boss of Atal'Dazar is Yazma.
Rezan is a giant dinosaur that stalks his ground in the centre of the first section of the dungeon. To access the boss, you need to jump down from the upper levels. The main thing to worry about here is his scream which will fear the players.
The tank needs to position Rezan near a post so that when Rezan is about to fear, everyone runs behind the post to prevent themselves being feared. Rezan will call upon smaller dinosaurs to add him so it is imperative that you hide behind the post so that you can be ready for the adds.