I feel your frustration, I have been farming Yevgney Nightcreeper for quite some time. According to the Wiki,www.wizard101central.com/wiki/Item:Spirit_of_Darkmoor%27s_Thorn#axzz4fIGp0vlj , he does drop it. There is a very low chance of it dropping, however. Given a number of items he drops, this could take quite some time. I am having problems with getting Malistaire's robe for my fire & storm characters. Just keep trying and you'll get it soon.