Unarmed Mastery (4e Feat)
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Unarmed Mastery [Ogrillon]
With a sickening crack, your knuckles twist the gnome's neck at an awkward and painful angle.
Prerequisite: 21st level, Ogrillon, Str 19, Con 19
Benefit: When you make a melee weapon attack with an unarmed weapon, you can score a critical hit on a natural roll of 19 or 20.