Luck

Luck is a character stat in both Golden Sun games. It increases your chance of inflicting a foe with a status inflicting problem such as Sleep and Stun and decreases the chances of you getting inflicted by the same.

Unlike your other Statistics, Luck does not increase as you level up. Luck cannot be temporarily changed during battle as well. The only way you can permanently boost an Adept's Luck is by using Lucky Pepper on them. That or setting a Djinni on them that boost luck.