Perfect Clarity 
Feat 18
Source Pathfinder Core Rulebook
Trigger You fail or critically fail an attack roll or Will save
You burn out all of your rage to ensure that your attack lands and your mind remains free. Reroll the triggering attack roll or Will save with a +2 circumstance bonus, use the better result, and resolve the effect. You then immediately stop raging.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
BarbarianThis indicates abilities from the barbarian class.
ConcentrateAn action with this trait requires a degree of mental concentration and discipline.
FortuneA fortune effect beneficially alters how you roll your dice. You can never have more than one fortune effect alter a single roll. If multiple fortune effects would apply, you have to pick which to use. If a fortune effect and a misfortune effect would apply to the same roll, the two cancel each other out, and you roll normally.
RageYou must be raging to use abilities with the rage trait, and they end automatically when you stop raging.