Weird. I know you can freezing trap or sap her but she's immune to poly? Prejudice. Will have to test fear and seduction.
Another option if you have a tanky enough healer (paladin/shaman) would be to tank her around a corner where your healer is still in LoS of your party but she can't see emperor to heal him. This used to work on private servers but retail scripting may be intelligent enough for her to run to into LoS in order to heal him. Needs testing.
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