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What are the special abilities the unique/champion monsters can have?
I have a Wizard, Witch Doctor and Demon Hunter, all of which are very early in Act I. Sometimes a small skull appears above my character. At other times (only with Odeg the Keywarden in the Fields of Misery?) my character is trapped inside a red column for a few seconds, or moves very slowly while a misty smoke moves around my feet. Are these curses from a monster? I've searched for a list or details of these, but I have not been able to find anything.