I used greater runes of warding and shielding...also waited to use last stand until last second...it was close but I got him down solo with my prot warrior.  He's immune to stun and interrupt so don't waste rage...mitigate his physical damage with block and demo shout...keep enough rage in pocket to deflect when  he starts hid chain...other than that I sundered x5 then slammed and retaliated when available and sundered for the x5 when they were not.