Seize the Moment (Feat)
You and your allies are poised to pounce whenever one of you scores a telling blow.
Prerequisites: Level 11
Benefit: When an ally who also has this feat confirms a critical hit against an opponent that you also threaten, you can make an attack of opportunity against that opponent.
Note: This is a Teamwork Feat, meaning it does nothing unless you and at least one other member of your party each possess this feat.