Marksman’S Shot (Ex)

Those who seek to slay with a single shot must have keen eyes and perfect poise. As an attack action, the slayer makes a single ranged attack at his highest attack bonus with a ranged weapon he wields. The target of the attack must be the slayer's studied target. On a successful hit, the slayer doubles the number of sneak attack dice applied to the attack; if the attack was not a sneak attack, this benefit does not apply.