I found this a week ago when we kept wiping on Hex Lord because of incompetent CCers.
You get up on top of the pillar in stealth pre-fight or normally post fight. Tag one or two of the melee adds (NOT the snake) and they'll evade bug you. They will eventually turn around and hit someone else but you can get aggro easily again.
Here's a video:
[ame]http://www.youtube.com/watch?v=MdyosZG9nTk[/ame]
SONG: Cookie Breath - MC Chris