Sneak Stab

A knife master focuses her ability to deal sneak attack damage with daggers and similar weapons to such a degree that she can deal more sneak attack damage with those weapons at the expense of sneak attacks with other weapons. When she makes a sneak attack with a dagger, kukri, punching dagger, starknife, or sai, she uses d8s to roll sneak attack damage instead of d6s. For sneak attacks with all other weapons, she uses d4s instead of d6s.