Flayknife (3.5e Equipment)

This wicked looking dagger is covered in wavy hooks and edges which make it look impractical, though it gives it a wicked bite if it strikes just right. Those proficient in the flayknife can subtract 1 point from their attack bonus (up to their BAB) and deal a -1 penalty against a creature's natural armor (down to a minimum natural armor of 0) as the knife is ideal at tearing away thick skin and hard scales. The penalty lasts until the creature is brought to full hp, makes a DC 25 Heal check as a standard action, or is subject to an effect which would regenerate limbs (treat flayed skin as a limb for determining how quickly it repairs itself). The penalty to AC overlaps, it does not stack.