It's taken me so many attempts and literally hundreds of gold in repairs to get this guy on farm (normal mode... haven't managed to drop Kael yet to unlock heroic... (sad panda)

general setup:
prot pali + 4 sham
spell damage sitting at around 550 or so on each sham, all ele.
no arcane resist gear on any (though having used potions, it does make a HUGE difference).

Pop bloodlust
Start out the fight like a normal tank and spank, all out aggro building on the pali - some healing but no nuking on the sham.
Pure energy spawns - run over and whack it with the pali
start light dps, keep pali topped off.
Pure Energy 2 spawns - run over and whack it with the pali
bloodlust 2
Start unloading DPS while keeping tank topped off
Pure Energy 3 will spawn right quick, i try to get this one with a shock, but if that fails a judge of righteousness works
AT this point the fight is pretty hectic... damage on the tank gets nasty with dots stacked so I pretty much run a Lesser healing wavex4, LB,heal,LB LB, heal type rotation.
bloodlust if needed
at 30~ish percent I stomp 4 fire eles and focus on keeping the paladin up
at 15% I start casting my group-hug chain heal (chain heal next party memeber key) which pretty much continues through the overload
loot and curse the silly loot table on such a frustrating encounter (and sometimes res the paladin since hes all stacked up with arcane DoT of doom)