Question regarding a ninja's "Hidden Master" & "Pressure Points" abilities.

[Valignatov]

I'd just like a little clarification on this if anyone has the knowledge.

Suppose I'm a 20th-level ninja with both the capstone ability "hidden master" as well as the ninja trick "pressure points". It says in the text of hidden master that...

"whenever the ninja deals sneak attack damage, she can sacrifice additional damage dice to apply a penalty to one ability score of the target equal to the number of dice sacrificed for 1 minute. This penalty does not stack with itself and cannot reduce an ability score below 1."

Pressure points says...

"Whenever the ninja deals sneak attack damage, she also deals 1 point of Strength or Dexterity damage, decided by the ninja. Unlike normal ability damage, this damage can be healed by a DC 15 Heal check. Each successful check heals 1 point of damage caused by this trick."

At first blush, it seems as though if I were to strike a foe who had, let's say 13 Dex, for SA damage, sacrificing all 10d6 SA dice to apply a 10-point penalty to his dex, as well as using PP to drop his dex by one more point, thus dropping his dex 11 points on the first attack. Then I proceed to attack twice more, getting SA twice more, again choosing to do 1 point of dex damage on each attack.
It would seem that I have reduced his Dex to zero using the combination of HM and PP. I actually don't think this is right. I think it works like this......

From HM I've given him a "penalty" and that's the key word to his Dex score. PP actually gives him "ability damage". So in the end his "Effective Dex" is 0, meaning no bonus to AC, nor ranged attacks, etc, but his "Actual Dex" is still 10, because the 10 points is just a temporary penalty to the bonus given by dex.
I'd actually have to hit him 10 more times with PP to really reduce him to zero dex, resulting in helplessness.

Am I right? What do you all think?

[Wesley Snacks]

While the fact it is a penalty can make things weird, I think the more relevant information from the ability is

"This penalty does not stack with itself and cannot reduce an ability score below 1."

What this means is if you do the -10 penalty, and then 3 dex damage, their effective Dex will be 1.
Because it would be 13-3 = 10
And then the -10 penalty cannot lower the score below 1, so it instead becomes a -9 penalty.

If you do 6 more pressure point strikes, it would still be 1.
Because it would be 13-9 = 4
And then the penalty can't lower the score below 1 again, so it instead is a -3 penalty now.

So you're right in saying that you need a lot of pressure point strikes to get him truly to 0, but you're wrong in saying that HM + PP = effective 0, because HM can never actually reach 0.

[Purplefixer]

You are correct. The penalty continues to retreat until you've hit him enough times to actually reduce his dexterity to 0 with the pressure points ability damage.

That being said, he IS at 1 dexterity for virtually the entire combat after that first hit... and that's pretty brutal. You might even want to switch tactics and go after his strength, allowing the wizard to grapple and pin him with impunity.

The humiliation alone should guarantee no reprisals!

[Valignatov]

Thanks guys; that about covers it. I thought it might be ridiculously OP if it worked the former way, but seeing that it works more like the way I thought it did (thanks a bunch Wesley for clearing things up further), it helps a lot.

Thanks again.

-V

[Kain Darkwind]

Also note that you need to at least deal 1d6 damage to activate pressure points. So the best you could pull off is -9 penalty and 1 damage in one hit, although if you anticipate two sneak attacks, a -10 penalty to Dex and 1 damage from pp is the more efficient choice.

Can you target Con with the penalty? A -10 penalty to Con immediately reduces the creature's hit points by 5xHD. On a 20HD creature, that's 100 hp gone in a single blow, and that doesn't include the damage you dealt with the base attack.