Intimidating Strike( Player's Handbook II, p. 79)
You make a display of your combat prowess designed to strike terror in your foe. Your stance, attack method, and demeanor demonstrate to your foe that you are capable of defeating him with little effort. Your intent is clear--if you decide to hit your foe, you could easily slay him.
Intimidate 4 ranks,
As a standard action, you make a single melee attack against your foe. You subtract a number from this attack equal to or less than your base attack bonus. If your attack hits, you can make an Intimidate check against the foe you struck, with a bonus equal to the number you subtracted from your attack roll. If this check succeeds, your opponent is shaken for the rest of the encounter. You cannot use this feat to worsen an opponent's fear condition beyond shaken.
A fi ghter can select Intimidating Strike as one of his fi ghter bonus feats.