Incompetent
Rules: When making skill checks for the named skill, the hero must reroll the best die and keep the second result. An adventurer cannot be Incompetent with more than two skills.
Prerequisites: No advantage Aptitude for the same skill; at most two disadvantages Incompetent.
AP Value: A/B/C/D skill: -1/-2/-3/-4 adventure points
Publication: Core Rules page 173