Eater Of Worlds Absence of Symmetry and Harmony bugged?

Is my client bugged or does he do a stupid amount of damage? My character sheet is above 75 allres, 6k life, 85% phys reduction, but both tentacles and laser beam attacks oneshot me. They oneshot people that have no problem clearing it solo. I've tried 4 or 5 quest version invitations, all with the same result at varying gear levels. What gives?