Storm caller is pretty awesome at golgoroth. The lock can even be gaze holder. Just stands on the edge and the lightening hits the orbs as well as the taken thrall. Also a Rezlock has saved us from sisters. 2nd relic holder was blown way the -blam!- away. We killed her but died as well. Not that we could have redone it but saved us like 10-15 mins. Locks are nice to have in the shade as well. I know you were saying that they don't have to take the hit but it's nice for oryx to slam and be back on the out side so damage can be done. I've heard you can just jump the echo and he will slam with out the jumper taking damage. I haven't tried it as I'd look and feel stupid if oryx just straight up killed me lol.