Solo last boss in Sethekk Halls for one of the pilgrim achievements called: Terokkar Turkey Time
Just did this as Arcane mage solo, very easily. One can skip all monsters. Use blink to get past narrow doorways with guards and follow the wall when you come to the first boss. In case you aggro, use invisibility. Last boss is very easy because Ikiss casts a shield which you can spell steal and it will practically make you immune from his attacks until he does the arcane explosion and you can steal it again.
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