I have no idea what is going on and same with my guild. i take alot less damage then the other tank we have form the logs i took 9million less melee damage. the shock barely hits me so that isnt the problem. its the back to back 150k+ hits when he has the 100% damage buff is what hurting me. Here is the log. we did eventually get him down after we switch tanks.
http://www.worldoflogs.com/reports/bkrpyl6d6het5fvr/
