As far as i can tell after some testing on tarant guards, backstab works in 2 ways. 1) If opponent is aware, then you will deal double damage...
I would like to notice that you don't get any EXP for killing with any of the subj. devices. That was pretty disapointing.
Lets imagine that i got 1 rank in persuation through leveling up, then i go to Kerlin' altar, offer a coin and gain it's buff. Will it be enough...
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