Most reliable way without messing up other factions is the inert potion quest in Erudin. Requires amiable with Craftkeepers, I believe. Goes extra fast if you get a Necro to root Slashin next to the quest giver
[You must be logged in to view images. Log in or Register.]. Be prepared for very tired fingers though. *edit to add or tons of orc scalps/goblin ears/gnoll scalps all work as well.