Does it give a flat 15% damage buff, or is it like the rogue's sneak attack where enemies need to have some cc condition for it to activate?

I've read that you need some form of cc for it to work but the description in-game does not state so, unlike the description for the rogue sneak attack.

I think it only activates same conditions as rogue sneak attack.

Correct. It is actually the same ability but with a reduced dmg modifier. Same as Skaen's "Baby Sneak Attack". Both do stack by the way, making a Priest of Skaen nearly as good with Sneak Attacks as a Rogue - but of course you need to pay for that with two talent points. 

Edited January 17, 20206 yr by Boeroer