Perk

In the SPECIAL character system, Perks are beneficial bonuses the player charecter picks up from experience.

Perk Rate is a Derived Statistic. It describes how often the character is allowed to pick a Perk. Character's Perk Rate depends on his race and traits.

Racial Perk Rate for humans is 3, which means that they can pick a new Perk every 3 levels. The rate is 4 for ghouls, super mutants and deathclaws, and 2 for dogs. Robots cannot pick Perks at all. The Skilled trait makes the Perk Rate slower by 1 level.

In Lionheart, the first Perk was taken at Level 2, not 3, but the subsequent Perks were taken every 3 Levels.