DanMcS said:
That's what I was thinking, but I would only allow it to convert 2 or 3 points of protection into amazing save. A single feat taking away the entire benefit of PL 10 protection vs PL 10 amazing save (10 power points, effectively) seems a bit strong. But then they could take the feat more than once, maybe, and combine effects.
I don't think it's that bad. Let's look at Minotaur:
Protection 10, Damage save 5.
Shot by a mook with +3L pistol - no damage. Protection is higher than the PL of the attack so it bounces.
Shot by mook with +3L pistol with (house ruled) Penetrating Attack - Protection 10 converts to Amazing Save - Dmg 10 plus Minotaur's normal +5 Damage Save for a total +15 damage save. The mook's attack DC is 15+3 = 18L. Minotaur needs a 3 or better to ignore the attack, a 1 or 2 on the dice gives him a lethal hit, just enough to make him notice it.
Shot by mook with +3L pistol with (house ruled) Penetrating Attack and it's a Critcal (+5PL) making it a +8L attack. Attack DC 15+8=23L vs Minotaur's +15 save. 8 or better to shrug it off, 3~7 takes a lethal hit, a 1 or a 2 results in a Stun for a round. Still no chance of dying, but now the PC is paying serious attention to the attacker. (This is if the mook is able to produce a critical vs the character's Def. If not figure the above could be a Power Attack example.)
If you only converted 1 or 2 levels of protection, the first two of the examples above would be the same Protection 10 or Protection 8 would still bounce the attack before the save, while the third would produce a damage save of DC 15 vs Minotaur's +7 damage save (5 normally plus 2 converted to AS - D. 8 or better to shrug it off, 3~7 takes a lethal hit, a 1 or a 2 results in a Stun for a round.
As for multiple levels of Penetrating Attack, I was thinking that they would have no effect but to counter possible multiple levels of Impervious (the Armor and Protection extra).
Like I said, I'll have to test it out in game to see how it goes. If it's looking too much like Penetrating Attack is becoming too widespead then I'll have to rethink the house rule.