By using the momentum of your weapon, you can use its weight to perform acrobatic maneuvers.
Prerequisite(s): Dex 13+, Operator Style, 3 ranks in Acrobatics.
BENEFIT
When in Operator Style, whenever you successfully hit a creature with a melee weapon attack, you can immediately make an Acrobatics check to Tumble through an adjacent square the creature threatens (up to 10 feet) as a free action that can occur outside of your turn. You can add half your weapon’s weight (up to your base attack bonus) as a circumstance bonus to the check. You can perform this feat once per round.