I'm playing solo as a hardcore Wizard on Torment IX, running Tal Rasha's with dual hydras. Usually when I encounter hard boss fights with melee bosses, I'm forced to kite and rely on my hydras + meteors to do the damage - and it works fine.
Malthael, however, is one of my hardest fights, especially in the 2nd stage of the fight, when he turns into a whirling thing and chases me around. He moves about as fast as I can run, the floor is full of bad things, and I can't teleport frequently enough to evade all that.
I just increased difficulty to Torment X and I'm fearful about approaching that fight. Any tips?