The Silver Hammer (3.5e Equipment)
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 The Silver Hammer
This hammer, which is actually a small silver +5 sledgehammer, once belonged to a cleric named Maxwell Edison, who was quite unhinged, murdering people who didn't expect it for usually trivial reasons if any at all. The hammer was used in sneak attacks, making a "Bang, Bang" sound when it hits a creatures head. The hammer, however, no matter how much it is used, remains gleaming silver, untarnished and unstained. The weapon, while not intelligent, tries to inspire those that hold it towards senseless violence.
The silver hammer is currently in a museum owned by a dwarf lord. He keeps it behind leaded glass, because he doesn't trust the thing.
 DM Notes
Our DM is a satirist, what can we say? Much like the vorpal sword, this was introduced as a joke. Our paladin used it, but he really hated it