Molten Shell Templar

Hi everyone. I'm just wondering if making a Molten Shell Templar is viable. I've seen a youtube video where (I think a witch) 1 shots Brutus with Molten Shell on Merciless using Elemental Equilibrium and Ice Nova to buff up the damage. If it is, I want to move onto my next question:

Can you build him with Pain Attunement? Survivability would have to come from energy shields, resistances and armour while using Blood Magic support to drop max life below 35% to permanently proc Pain Attunement. If necessary, assume that Pain Attunement can be obtained via a unique. How would this Templar have to be built to reliably survive and still kill things?

While I'm not asking other people to do my theory crafting for me (I'm perfectly capable of spending 15 minutes in the skill tree tweaking), I have no idea how much survivability you need to hold out against Merciless mobs or how much damage you need to drop them quickly enough... and this ratio is important to making the build work. The main focuses would have to be getting enough energy shield and enough +fire damage from the skill tree while equipment takes care of spell damage, armour and resistances.

For the build you are referring to, take a look at this: http://www.pathofexile.com/forum/view-thread/90885