Wow - Solo Monk - Sanctum of Domination (Mythic mode) - Roh-Kalo - 10.2.7 

This boss is hard for DD (impossible i think) and so easy as a tank.
This boss has wipe-mechanic that we can't do solo but this mechanic deals only 300k damage per 2 secs that we can survive as a tank.
Just tank the boss in def's gear and he will die, slowly.
It's all =)