Energy Vulnerability vs Energy Resistance

[Joe Mathos]

One of my characters recently received a boon that gave him electricity vulnerability as a downside to the boon. He also has a Mk 2 Electrostatic Field. How would you calculate the damage he would receive from an electrical attack?

For example, if he is attacked for 12 damage, what would he take?
12 * 1.5 EV - 10 ER. 18 - 10 = 8?
Or 12 - 10 ER * 1.5. 12 - 10 = 2 * 1.5 = 3?

[Pantshandshake]

I'd go with option B, as a creature with vulnerability takes 1.5x damage, as opposed to all damage targeting them being increased by 1.5.
Thusly, I wouldn't include damage 'blocked' by resistance int he equation.

[Lethallin]

I believe the DR/ER applies and then the vulnerability.

DR/ER reduces the amount of damage before you take it, vulnerability increases the damage by 50% as you take it.

Alien Archive pg 158 wrote:

VULNERABILITY (EX OR SU)

The creature takes half again as much damage (+50%) when it takes damage of a specific type.

CRB pg 264 wrote:

Energy Resistance

A creature with resistance to energy has the ability to ignore some energy damage of a certain type (acid, cold, electricity, fire, or sonic) per attack.

I think the key here is the phrase "when it takes damage", which is about as late in the calculation process as possible.

[Garretmander]

I've always run it as vulnerability then DR/ER, but that's probably just the order of operations how I add things up. Also, it typically helps the PCs as they're less likely to have a vulnerability.

[Eric Clingenpeel]

I agree with Lethallin. Its how I've always done it as the resistance should be figured in before you figure damage.

[Joe Mathos]

I thought it would be Option b as Lethallin and Eric have stated. I figured that you would resist first and then whatever got through would be multiplied. I just wanted to get some clarification.