Mighty Death-Blow (3.5e Feat)
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 Mighty Death-Blow [General]
You can cleave heads in a single mighty blow.
Benefit: For any weapon that you have Improved Critical with, the threat range of using a vorpal version of that weapon becomes 19-20 for a decapitating effect.
Normal: A character with a vorpal weapon only scores a critical on a roll of natural 20.