Where does Armor Piercing apply?

[Mastermind]

This came up in game:

 

Someone was shot with an AP Killing Attack. The GM halfed his rPD and did BODY as usual, but then he declared that the STUN damage (Killing Damage x STUN multiplier) was also cut in half. The player began to argue.

 

Who is correct?

[Steve Long]

I'm not sure if I understand the question, so please post a follow-up if I don't address your problem.

 

AP does not halve the STUN damage caused by the attack, Killing or otherwise.

 

AP does halve the defenses (both Resistant and Normal) the target may apply to the STUN damage of the attack, be it Killing or Normal Damage.

 

Example: Drogar is hit with an HKA that does 10 BODY, 30 STUN. Drogar's PD is 8 -- 4 Normal PD, and 4 PD Armor. Drogar takes 8 BODY (10 - (4/2)) and 26 STUN (30 - (8/2)).