Ability damage is always an annoyance, but it is particularly dangerous when a score is reduced to zero—this makes the affected creature helpless (all incoming damage is multiplied by 1.5). Red and purple creatures can never be rendered helpless.
Ability penalty is similar effect, but are generally more temporary and often work on red and purple named enemies. Ability penalties, e.g. from ray of enfeeblement do not stack - only the highest penalty applies. Ability penalty and ability damage do stack.
Notes on how this applies to monsters:
- Works the same as it does on players versus regular monsters.
- Red named creature can suffer ability damage, but only up to 10 points, and may never reach a score of 0 in any stat.
- Purple named creatures are completely immune to ability damage.
- Creatures with Epic Ward are resistant to ability damage.
Ability damage automatically regenerates at a rate of 1 point per minute (applies to both monsters and players).
Changes in ability scores impact many statistics of both player character and monsters, including hit points, carrying capacity, saving throws, skill checks, access to spells, etc.
- Constitution damage has a particularly lethal effect in reducing both your current hit points as well as total hit points. In general, every 2 points of Constitution damage reduce a creature's hit points by a number equal to its level (or HD in the case of monsters). Other important statistics affected are the Fortitude saving throw and the concentration skill. Reducing Constitution to 0 stuns the affected creature for 6 seconds.
- Strength damage can be equally dangerous. In addition to the obvious effect of reducing your melee attack rolls and damage rolls, it affects your carrying capacity and can render your character encumbered (reducing your movement speed, some skills and possibly your armor class).
- Damaging mental ability scores can cause your character to lose the ability to cast spells. Many skills are also affected. Damaged Wisdom reduces your Will saving throw.
Healing Ability Damage
Ability damage regenerates at a rate of 1 point of each ability score per minute. Some monsters (especially bosses) recover ability damage at a much faster rate. Ability penalties disappear when the spell that caused them expires.
There are other ways to recover from debuffs and other ability damage.
- The spells Restoration, Restoration, Mass, Greater Restoration, or Heal cure all ability damage.
- The Axe of Famine casts Greater Restoration on vorpal.
- Lesser Restoration restores 1d4 points of ability damage and dispels all ability penalties.
- Panacea dispels all ability penalties.
- Regenerate and Regenerate, Mass heal minor stat damage over time.
- A Cleric's AoE Positive Energy Burst restores ability damage.
- Shintao Monk Healing Ki finisher with Difficulty at the Beginning toggle.
- Get a counteracting buff, such as Bull's strength for +4 Strength. This does not heal the damage but it can help you overcome the effect.
- Resting at a rest shrine removes all ability damage.
- Tavern regeneration.
Sources of Ability Damage
- Weakening prefix and Enfeebling suffix on weapons causes STR damage
- Maladroit prefix and Bone breaking suffix on bludgeoning weapons causes DEX damage
- Wounding prefix and Puncturing suffix on piercing weapons causes CON damage
- The greatsword Insanity causes WIS damage and can be useful vs. self-healing mobs
- Tchurvul's Kukri (CHA damage)
Spells and effects:
- Chill Touch (STR)
- Poison (spell) (CON)
- Spider Poison (STR)
- Ego whip of Mind Flayers (CHA)
- Melee attack of Quori Spiders (e.g. in The Prisoner)
Sources of Ability Penalties
Spells and effects: