In ACT2 Hell (and normal before but didn't report yet)

finding Zul Kullu's blood at desert

I found randomly (a)unkillable monster(s).
I cannot hit them but they can hit me!!
I must run to portal to go back town or I will die.
I must leave game and reload map again.
This is not happen so often but so annoying.

I am witch doctor.Main attack is zombie bear. I am using HEX.
http://us.battle.net/d3/en/calculator/witch-doctor#efUdRP!cTU!ZcZZaZ
Edited by BlueDrop#1940 on 5/30/2012 12:04 AM PDT