This boss was a freaking beast. i reforged my whole tankgear to dps used dps gems dps trinkets and then on my first try after doing all this he enraged at 35%...
So i found out that this boss is ALL about CD timing and smart stacking. I even kept 1 trashmob for the whole fight to give me some vengeance.
you can bounce the sphere as much as you want but it always just stacks till 10 so after 10 bounces he has to eat it. bouncing 11 times would be stupidity but always bouncing 10 times also isnt smart because he gets his stack AFTER he eats the sphere, so it makes sense to dont go up to 10 shortly before end.
Summoning Army of the Dead near the end and using Str pot so that both will run out just before he enrages was very necessary because of his many stacks near the end.
He enraged at 8% and hit for around 500k while enraged. with all CDs up i made it to survive long enough to kill him while dealing around 600k-800k dps in the last few secs of the fight thanks to ridiculous high vengeance.
Everyone who can kill this boss with same or less gear then me deserves my highest respect.