Regarding the Rogue Talent “Resiliency”

Question

I'm not exactly sure how Temporary Hit Points work in Pathfinder but here's what the Talent states:

Once per day, a rogue with this ability can gain a number of temporary hit points equal to the rogue's level. Activating this ability is an immediate action that can only be performed when she is brought below 0 hit points. This ability can be used to prevent her from dying. These temporary hit points last for 1 minute. If the rogue's hit points drop below 0 due to the loss of these temporary hitpoints, she falls unconscious and is dying as normal."

I'm assuming that means that if I were hit by something for 10 points of damage and I'm only level 7, my hit points still fall below 0 to -3 and I'd still be unconscious. Or does it mean that, after the hit, I receive these hit points and they last until depleted or the 6 rounds have gone by?

Answer 1

Your 7th level rogue has 1HP. Rogue takes 10 points of damage (which brings her to -9HP). In response, the talent activates and gives 7tHP (bringing the total to -2). You are still unconscious, but you now have 6 rounds to have a buddy pour a healing potion down your throat, attempt first aid, or for you to stabilize normally.

Assuming instead that the damage is 5 points (instead of the 10 you use in your question), the pattern goes: 1HP, -5HP from attack (to -4). Resiliency kicks in giving 7tHP (bringing total to +3). Now the Rogue has the opportunity to withdraw, and drink the healing potion in her backpack. Or perhaps beg a heal spell from the Cleric.

Answer 2

Temporary hit points are only a cushion against future damage, not an actual healing. If a character drops below 0, granting him/her temporary hp doesn't make him/her conscious nor stabilized.

The wording of the talent seems confusing, much because Pathfinder doesn't specifically defines immediate interrupts and immediate reactions.

The intent of the talent seems to be preemptive:

[...] This ability can be used to prevent her from dying. [...]

So it should grant temporary hp before the damage lands on the rogue, even if a previous statement suggest it is a reactive:

[...] can only be performed when she is brought below 0 hit points. [...]

But this sentence alone negates the beneficial effect of the talent. I'd use the conditional clause: "when she would be brought below 0 hit points", thus making the sentence a preemptive trigger.