Target of Opportunity

Combat Teamwork

You and your allies pelt your enemies with a deadly barrage of missiles.

Prerequisite: Point-Blank Shot, base attack bonus +6.

Benefit: When an ally who also has this feat makes a ranged attack and hits an opponent within 30 feet of you, you can spend an immediate action to make a single ranged attack against that opponent. Your ranged weapon must be in hand, loaded, and ready to be fired or thrown for you to make the ranged attack.

Source: Ultimate Combat