Toughness: In the original Fable, Toughness increases the Hero's natural armor, or defense the Hero has when naked. However, in the sequel, Fable 2, Toughness increases the Hero's hit points.
Physique: This ability allows the Hero to wield heavier weapons and swing melee weapons harder. In Fable 2, this ability is what causes the Hero to bulk up.
Health: Only appearing in the first game, Health increases the Hero's Hit Points. As stated above, Toughness replaced this ability in the sequel.
Brutal Styles: Only appearing in Fable 2, Brutal Styles gives a special ability with each advancement starting with: Block, Flourish, Chain Attack, and Reversals.
The leveling system in Fable 3 is changed to Road to Rule, removing the three Hero Traits.