Base Ability Scores in Underrail serve as the base for your character and consist of seven attributes: Strength, Dexterity, Agility, Constitution, Perception, Will and Intelligence. Certain functions, items and actions require a minimum score of a certain base ability to be used or performed, while some items, such as foods, temporarily boost them. Some feats also require a minimum score of a certain base ability (and skill level) to be picked and used. Each base ability is set to a default of 5 and has a maximum of 10 during character creation.
You gain a base ability point every 4 levels. Theoretical maximum base ability score is 20, although not reachable with the current level cap.
Every point in base ability above 4 increases the effective value of dependent skills by 8.5%, while every point below 4 decreases it by 10%.