The first boss of Aberrus has been defeated on Mythic difficulty by <The Early Shift>, taking down Kazzara, the Hellforged after 23 pulls! Race watchers may remember that <The Early Shift> also achieved the first kill of Vigilant Guardian in Sepulcher of the First Ones. Congratulations!
Mythic Kazzara VoD
In terms of composition, they used:
2 Tanks: Brewmaster Monk, Blood Death Knight