Power Critical
Prerequisites: Power Attack, BAB +4
Benefeit: For every point you reduce your weapon's threat range, you may increase its critical multiplier by one. This adjustment is made on your turn and lasts until your next turn. Your weapon may not have a threat ranged smaller than 20.
Power Critical is not very good. You can basically use it to convert your longsword into a battle axe. The best use I could think with it might be to swing a scimitar or rapier with 1d6 19-20/x3. You are still swinging lower damage than a longsword/axe, but you have very good critical math. You could alos use this feat to get milage out of keen and improved critical.