Creativity and Luck are both cheap (1 pt) racial ability picks that give seemingly large bonuses (+25%), but it's not very clear how they work or how much impact they have.

Is it a 25% factor increase to some existing chance - ie: your base chance was 10%, so now it's 12.5%? Or an overall increase of 25% - ie: you base chance was 10%, now it's 35%. Big difference in effect!

Does anyone swear by either of these abilities, or are they mostly ignored?