Does anyone know where she is. You have to bring her head back to the djinn.

She's the lady who sells potions in the cabin in the North East corner of the Druid Grove. If you go there before you accept mission from Djinni, she won't act like anything other than a merchant, but once you have accepted the mission, she attacks you onsite.
I speak from experience;I didn't talk to the Djinni until after I'd finished the Druid Grove and looked everywhere with no luck, and then someone here, on the message board, had to help me too. Good Luck

Thank you I did like you