Note that during the events of book 1 we rarely, if ever, had hard numbers for what skills were doing. For the most part it was a lot of trial and error. As such, this page is essentially full of unmarked minor spoilers. Proceed at your own risk.
Moderate spoiler - Hero progression, chapter 9
Hero skills are granted only to the hero class and only if they demonstrate a mentality that is applicable to it.
Hero skills do not have a level.