Discussion:My Discussion/What is a "character ability based on class levels"?
From D&D Wiki
What is a "character ability based on class levels"?
Such is the description of the abilities for which UA bloodline levels are added to the class levels to determine the features of the ability. Caster level and the DC of the monk's stunning attack are given as examples.
This is a potentially useful finesse for multiclassed optimized builds. For example, a character with three bloodline levels plus two levels in psion, five in wizard, and ten in cerebromancer would enjoy a ML/CL of 15/18, significantly greater than could be achieved in the absence of the bloodline level's enhancement.
My problem with this rule is determining what constitutes an ability based on class levels. Clearly, you don't gain any new class abilities. You don't gain feats, powers, or spells. But which existing class abilities improve? Is it any ability which improves in a predictable fashion based upon character level?
Pretty clearly if the ability specifically references class level in the description, it's in. Laying on hands, monk spell resistance, artificer effective caster level, etc. But what about the abilities of one's familiar or animal companion, the monk's bonuses, the rogue's sneak attack? Those also improve in a predictable fashion according to class level.