I hear ya. I did horrible on this fight as well. I think it was the renew because it felt like I had virtually no DPS on the shadow mob.

I will have to try the purge tactic. That was mentioned in other strats I read as well. I did read one suggestion to kite the mob around and that causes Paletree to follow you as well since she is linked ot the shadow somehow. I am not sure if this stops her from casting though.