Ok basic situation is, rr5 ability when used causes an orb like static temptest to appear where your victim was (assuming orb is temp graphic for a cauldron which will come in a later patch) this orb then sits there for 5 seconds and then detonates doing 500 energy (surely should be heat?) damage to 350 radius around the orb - the 500 damage is before resists so normal dmg on unresist buffed people is around 440-450 and on resist buffed ubergroups around 250-300. So, an ok RA but not great.
HOWEVER atm there is a bug that is seemingly random where when you use the RA it will spawn MORE THAN 1 orb (cauldron). I've used this ra about 10 times and 2 of those 10 times it's summoned 2-5 orbs, which all in turn detonate for the same 500 dmg before resists. Once was when albs were rushing a tower i was in after getting gates down, i thought i'd try the ra out and popped it on the people outside the gate (about a fg) and 5 orbs appeared and killed all the albs instantly 5 seconds later and looking at my status window i did ~400-450 dmg per person in the radius 5 times at the same time, so 450*5 at the same instant.
Screen of dmg from 5 orbs (2 pics in sequence):
http://www.btinternet.com/~ajrdriver/sshot088.jpg
http://www.btinternet.com/~ajrdriver/sshot089.jpg
Also I've had it do any number from the intended 1 orb to 5 orbs at any one time, i dont know what makes it do more orbs or less it seems to be random when you use the RA.
Expect a fix soon since a warlock 1 shotting a fg of albs with 1 RA is definatly not intended