In Pathfinder, ability damage does not reduce your score in any way. It just gives you penalties.
If you have a constitution of 18, and take 16 constitution damage, you constitution is not 2. It is still 18, with some hefty penalties on certain checks.
Diseases, poisons, spells, and other abilities can all deal damage directly to your ability scores. This damage does not actually reduce an ability, but it does apply a penalty to the skills and statistics that are based on that ability.
Do you mean ability drain?
Ability drain works differently then ability damage. Ability drain actually does reduce your score. A person with 18 constitution who has taken 16 points of constitution drain does have a constitution of 2, and will die if his hit points are reduced to -2 or lower.
If the same person had instead taken 16 points of ability damage, he wouldn't die until his hit points reached -18, as his actual constitution score has not changed.
This is still an incredibly dangerous situation, as the penalty from Constitution damage would apply (along with the character's negative hp total) to the DC 10 Constitution check to stabilize.
And it's DC 10+negative hp..
You may want to phrase that better. If I'm at -5 hp, according to your statement, the DC is only 5.
You don't die until you reach -10 hp in Pathfinder, regardless of your constitution score. Jeraa is correct that with ability damage you could go down to -17 without dying (given an 18 Constitution originally). And with ability drain you could still go to -9 without dying.
Stabilize DC: 10 - [current hp]. Add your Constitution modifier to the roll, or subtract it from the DC (e.g. At -5 hp and a 14 Con, 10-(-5) = DC 15, roll d20+2 to stabilize (15-2 = 13 needed).
Just to be clear: the DC to stabilize is DC 10. There is no modifier to the DC due to your constitution score or negative hitpoints. Those modifiers are applied to the check itself. DC 10 Con check with the roll being: 1d20+(con modifier)+(negative hitpoint value)
On the character’s next turn, after being reduced to negative hit points (but not dead), and on all subsequent turns, the character must make a DC 10 Constitution check to become stable. The character takes a penalty on this roll equal to his negative hit point total. A character that is stable does not need to make this check. A natural 20 on this check is an automatic success. If the character fails this check, he loses 1 hit point. An unconscious or dying character cannot use any special action that changes the initiative count on which his action occurs.
Regarding Constitution Damage, if I normally have an 18 con and have 16 points of constitution damage I suffer the following effects:
-8hp per level-8 penalty to fortitude saves.
-8 penalty to any check involving Constitution (such as a Stabilize check).
What does not happen: My Constitution score does not change. I still die when I reach -18hp and not when I reach -2hp.
For every 2 points of damage you take to a single ability, apply a –1 penalty to skills and statistics listed with the relevant ability. If the amount of ability damage you have taken equals or exceeds your ability score, you immediately fall unconscious until the damage is less than your ability score. The only exception to this is your Constitution score. If the damage to your Constitution is equal to or greater than your Constitution score, you die. Unless otherwise noted, damage to your ability scores is healed at the rate of 1 per day to each ability score that has been damaged. Ability damage can be healed through the use of spells, such as lesser restoration.
Constitution: Damage to your Constitution score causes you to take penalties on your Fortitude saving throws. In addition, multiply your total Hit Dice by this penalty and subtract that amount from your current and total hit points. Lost hit points are restored when the damage to your Constitution is healed.
- Gauss
Thank you Gauss.
You don't die until you reach -10 hp in Pathfinder, regardless of your constitution score.
Incorrect.
When your hit point total reaches 0, you're disabled. When it reaches –1, you're dying. When it gets to a negative amount equal to your Constitution score, you're dead. See Injury and Death, for more information.
Dead
When your character's current hit points drop to a negative amount equal to his Constitution score or lower, or if he succumbs to massive damage, he's dead. A character can also die from taking ability damage or suffering an ability drain that reduces his Constitution score to 0 (see Special Abilities).
You die when you have negative hit points equal to your Constitution score. If you Constitution score is 2, then you die at -2.
Thank you gauss. So we no longer have the 10% to stabilize at negative hit points. That's good to know, I've been playing that wrong the current and last campaign.
Another question, if you take damage to your spellcasting attribute, could you still cast spells as if you didn't take the damage? For instance, I'm a wizard and my int drops to 8, could he cast spells at all?
Thank you gauss. So we no longer have the 10% to stabilize at negative hit points. That's good to know, I've been playing that wrong the current and last campaign.
Another question, if you take damage to your spellcasting attribute, could you still cast spells as if you didn't take the damage? For instance, I'm a wizard and my int drops to 8, could he cast spells at all?
Again, ability damage does not reduce your score in any way. An 18 intelligence wizard who has taken 10 points of Intelligence damage still has an Intelligence score of 18. He just takes a -5 penalty on Intelligence based checks, which does mean his save DCs for his spells will be lower. But he can still cast those spells.
Now, if that had been ability drain, then his score would have dropped to 8, making him unable to cast his wizard spells.
Thank you gauss. So we no longer have the 10% to stabilize at negative hit points. That's good to know, I've been playing that wrong the current and last campaign.
Another question, if you take damage to your spellcasting attribute, could you still cast spells as if you didn't take the damage? For instance, I'm a wizard and my int drops to 8, could he cast spells at all?
i think, for clarity sake, you should make sure you understand there is a huge difference between ability damage and ability drain
in your example a wizard with a 16 int who has taken 2 points of int DAMAGE is still capable of casting 6th level spells. the same wizard with 2 points of int DRAIN(instead of damage) cannot cast 6th level spells, since his int is actually 14 for purposes of spellcasting.
asthyril: I have taken a great deal of intelligence damage, and since that applies to my intelligence check to learn something new, it's good that you explained that to me ;)
Aability penalties function just like ability damage, so if you 16 Intelligence wizard is suffering from a -4 penalty to Intelligence, he can still cast 6th-level spells.
Also keep in mind though that a great many spells that bestow mental penalties, such as touch of idiocy, SPECIFICALLY STATE that the penalty interferes with your spellcasting. These are an EXCEPTION to the GENERAL RULE, though it appears to be a common one. Certain other spells, such as feeblemind, are neither damage nor a penalty. They simply change your ability score to a set value (which can interfere with spellcasting).