Ive tried this a few times on Zul'jin, and so far it seems like no1 else knows about it - tell if im wrong, and ill wtf-delete this post
Phase 3 is a b*tch since all those tornadoes moves around and does alot of dmg.
I found a very small spot under Zul'jin (when he transforms into the eagle), where the tornadoes doesnt hit you - not even if they pass right thru you.
Its right underneath him - moving just a tiny bit to either side will make the tornadoes hit you again.