Intimidate question

[Saldiven]

I seem to remember reading an effect that could allow multiple uses of Intimidate on the same subject(s) to increase the level of debilitation inflicted. (Shaken becomes Cowering or Frightened, for example.)

I can't remember if it was a weapon enhancement, a class ability, a Feat, or what. Can anyone point me in the right direction for this?

[KainPen]

Hell Knights class ablity: Fearsomeness (Ex; any order): A Hell knight who uses the Intimidate skill to cause a creature within 10 feet to become shaken can instead cause that creature to become frightened. only thing i can think of that allows the increase of any kind.