What lvl/stats are needed to fight Act 2 Boss Ruthless? (Templar)

Hey guys, just wanted to know, at least roughly, the stats needed as a templar to fight that Boss. Im lvl 47 1000hp,
300dps, 40%dmg reduction, 11% evade, 38%blook. Resistances 58/75/36 (fire/cold/lightning), but im gonna get some lightning resistance armor and bring that res to 75 if possible.
Anyways, if you want, you can answer the same question but for merciless difficulty also, so i already know in advance (that would help a lot).
Any help will be appreciated.

I fought this guy in that difficulty yesterday. First off, all my resists were capped and I had 1500 HP. I only play hardcore.

- Fire mallet hit me once (oops!) and took me to about 30% life. Good data point for you.
- Laser hit took me to about 70% life, no big deal but if he goes into the cave-in right after you take a laser shot you need to drink a %armor potion. Rock hitting you while shocked = ouch.

In fact i dodged all the rocks, so I can't speak to what they hit for.

I am also pure armor/life templar build, no ES. Yesterday I had about ~1500 armor, but I'm not sure if the mallet is a split phys/fire attack or just straight Fire dmg.

Lightning resist ....

Speed is good also you do not want to be by him when teleports back ...

Also if you have a decoy totem use it if not for the boss at least it holds up his minions.....

Thanks a lot zakaluka, that was very helpfull, specially knowing the damage he dealt to you. Thanks Tallonz also for the tips. Ill guess ill cap my light resist and improve a little my gear.

since I am around 300 elemental dps with my witch on the end of cruel (right before VO) you may expect a long fight against him with that probably low damage in Ruthless...