The Coren Direbrew encounter is a fairly easy boss fight. You can queue for him via the dungeon finder tool upon reaching level 99.
After Direbrew is killed, any remaining adds will despawn. For the first kill each day, you will be rewarded a Keg-Shaped Treasure Chest. Direbrew also has a chance to drop one of the following trinkets each time he is killed: Coren Direbrew
Criterion of Direbrewfest.