Ability Drain

More severe than ability damage, ability drain reduces your ability score permanently. Note that this affects your score directly instead of penalizing your modifier, so 1 ability drain changes your modifier if your original ability score was even, but not if it was odd. Modify all statistics related to the ability’s new value. This might make you lose skill ranks along with Resolve Points, Stamina Points and other bonuses gained from having a high ability score. If you take ability drain in the middle of a battle, the GM might have you treat it as damage until after the fight so recalculating your statistics doesn’t slow the game. Ability drain doesn’t heal naturally but can be healed by the restoration spell.

In general, if any ability score is reduced to 0 from ability drain, you fall unconscious. If that score is Constitution, you instead immediately die.