I use iron maiden + clay golem for normal bosses. Keep iron maiden up on the boss and just re-summon the clay golem on top of it. (iron maiden = 200% reflected damage) They kill themselves for me.
Grats on the diablo kill.
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I found this in act 3. Put my stealth on my merc so I can swap to it if I need it.
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I also completed the Insight runeword for my merc. I got a lvl 16 Meditation aura.
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Level 38 atm at the start of Act 2. I'm slightly under level for where I'm at due to it being hardcore. Still have not found a Dol or Io runes to make White. Or a Wand with 2 sockets that has +3 bonespear or something else useful.