I'm not aware of any slay undead effects at all (other than the paladin AAs). There are some procs that affect undead only, but I think those are also paladin/cleric only weapons. Not sure about augs. It's possible (probable?) that there are some necro/SK items that have undead only effects, but again those are going to parallel the classes own abilities.
I'm not sure why you'd want this anyway. Classes compliment each other by bringing different things to the table. If one person is already playing a paladin, just let that character do the anti-undead stuff. Bring other classes in for their own special abilities. Trust me, there will be lots of things you'll need to kill that aren't undead, so the minor benefit you'd gain in a small amount of cases isn't going to amount for much in the larger scheme.
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King Nobby wrote:
More words please