Alten's Soul Harvester (3.5e Equipment)
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Alten's Soul Harvester: Alten's Soul Harvesters are Keen Greater Wounding Kukris that can cast Binding on a critical hit.
Alten Thorngage noted that the artifact "gripsoul" was quite weak for the expense of creating one, so he made his own custom kukris that emulated them. Only two exist, and can be destroyed only by throwing into a volcano, with a Consecrate spell on it, then fishing it out three weeks later (by hand) and smiting it with at least a 20th level paladin with a vorpal weapon.
+1 Greater Wounding Keen Kukri's, that cast Binding (minimums containment) whenever it scores a critical hit. It also creates a platinum piece to contain the unfortunate victim.
Alten created them through normal means but then inscribed them with specialized runes of his own design, to permanently imbue them with the ability to trap souls.
Strong Transmutation, Evocation; CL 15; Weight: 2 lb.