Wow - Solo Monk - Sepulcher Ones (Mythic mode) - Lihuvim - 10.2.7

This boss is easy but he has one-shot mechanic that we need to deal with.
This boss sometimes can kill you if you are only one player in a room, so we need to know then we need use a def's CD.
I used DBM to check it and pressed def's CD every 30-40 secs of a fight.
Just survive this oneshot and boss will die.
It's all =)