Sneak of Shadows [Multiclass Rogue]
Prerequisite: Dex 13
Benefit: You gain training in the Thievery skill.
Once per encounter, you can use the rogue’s Sneak Attack class feature.
Slaying Action
Heroic Tier
Prerequisite: Rogue, Sneak Attack class feature
Benefit: If you spend an action point to take an extra action and have already dealt Sneak Attack damage during this round, you can deal the extra damage a second time during this turn.
I respectfully disagree.
If you have the sneak of shadow feat and you AP the same round as you have used your 1/encounter sneak attack, I see no reason why Slaying Action should not grant you the extra sneak attack damage on the AP attack, of course assuming all the other conditions to apply Sneak Attack are met.
I'm with Mouseferatu. As a multiclassed Rogue, you only get Sneak Attack once per encounter. As a regular rogue, you only get Sneak Attack once per round. Slaying action lets a regular rogue break the "once per round" rule, but my interpretation of it is that it does NOT let a multiclassed rogue break the "once per encounter" rule.
If I am multiclass rogue with Sneak of Shadows, I meet all prerequisites.Slaying Action
Heroic Tier
Prerequisite: Rogue, Sneak Attack class feature
If I with my 1/encounter sneak attack deal sneak attack damage during a round, I meet this part.Benefit: If you spend an action point to take an extra action and have already dealt Sneak Attack damage during this round, you can deal the extra damage a second time during this turn.
Benefit: If you spend an action point to take an extra action and have already dealt Sneak Attack damage during this round, you can deal the extra damage a second time during this turn.
However, the feat does not specifically mention that the second extra damage has to meet the prereqs for sneak attack (such as combat advantage). So it could be interpreted that I can automatically get sneak attack damage on my next hit that round, regardless of whether I have CA or not.
But since I don't believe that is the intent of the feat, I would then argue that the rogue must still meet all of the requirements to perform a sneak attack to obtain that second damage. One of those is the ability to sneak attack. Since the multiclass rogue now longer has the ability to sneak attack (since he's 1/encounter SA is exhausted), I would say he doesn't get the extra damage.