I guess you guys all know the bloodstone hench mission (yes that one with the seeds to create bridges etc.)
ok now you should also know the bonus of that mission (right, the one where you have to escort some elder druids).
they tell you not to harm any of the guardians and if you do the bonus will fail. the trick is to finish the bonus by not attacking but after you got it attack the guardian that is standing right in front of you. if he dies there are like 4 nightmares that get out of him (they are strong so be careful).
they drop really nice necro wands and idols etc. (yellow, purple whatever you already dreamed of)
i got 1 purple staff of enchanting, 1 yellow of skel slaying with nice adds and a purple idol +12 nergy and life bonus so far and i only did that once
so good luck and have fun with farming