You carefully line up a ranged attack, timing it precisely so that you hit your opponent when his guard is down. When your target is busy dealing with an ally’s melee attack, you strike.
Prerequisites: Point Blank Shot, Precise Shot, base attack bonus +4, skirmish or sneak attack ability.
Benefit: By firing just as your ally connects with a blow, you take advantage of the distraction to strike the same enemy when his guard is ruined. If you ready a ranged attack to occur when an ally strikes a particular target, and your ally succeeds, that target loses his Dexterity bonus to AC against your attack.
Special: A fighter can select Deadeye Shot as one of his fighter bonus feats.
Source: Player’s Handbook II, page 78.