I don't understand how...

maybe it was made with some silver... but that's for the werewolves

Yes. I was a little confused on how that was the ultimate stopper for the undead. I thought I had missed something.

The only thing I can suppose is that only a zombie can kill another zombie, regardless of the method or weapon used. If that was what they were going for, they could have done a better job explaining it...

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"Little do they know how little I know about the little there is to know." - Neddy Seagoon

I'm glad I'm not the only one who was confused by that.