Damage is going to be very stat- and gear-dependent. But with a successful backstab+sneak combo (with Guerilla), you should be getting a 4x damage multiplier. Couple that with the fact that daggers hit twice, and you end up dealing 8x stated weapon damage (plus any bonuses from abilities/gear) with a single attack.
For reference, my level 7 shadowblade deals around 180 damage per hit (so 360 damage total per attack) to same-level enemies with a backstab+sneak using a dagger with a base damage of somewhere around 40-60, iirc. Also my guy has nowhere near an optimal build in terms of stat distribution and gear. So I have no doubt you could see higher numbers at the same level.
Okay yeah that pretty well add's up, however what I meant was compared to say a bow/xbow user or 2hand char using their abilities. For instance I would say a bow/xbow user at level 7 would probably be doing around 100dmg a hit or so depending on gear, then couple that with arrow spray and the damage is ridiculous as that can hit 3-4 times.
However this is good information and I will have to do some further testing.
