Giselda the Beautiful

Giselda, before she aged. I wonder if she'll still shapeshift when we beat her up.

Killing her is an objective for the level 92 quest To Capture Gul'dan, in which you are supposed to capture Gul'dan by "any means necessary."

Possible Spoilers, Definite Speculation: It would seem that, at some point (likely after and/or due to these events), Gul'dan decides to elevate himself to a new position, with a fancy new title.

She didn't deserve what she got.

For those interested in obtaining her staff, it is the [item=122353] which can be enchanted by Spellpower.

Other similar models are:

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• [item=65485], a reward for completing [quest=2743] in in Shadowfang Keep.
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• The Bringer of Death, a drop from the trash in various TBC dungeons and raids.
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As per the gear, it is the Replica Dreadmist Set which can be purchased from [npc=57983] in Darkmoon Island with [currency=515].