Nope , that bonus is a normal parry damage by shield or stealth , so applies as always , thats why knife have huge critial damage ( but second attack sword have more )
And knife have none of block armor so is impossible to parry with it haha

If you parry with a shield then the shield's parry bonus applies, not the knife's. The parry bonus is a multiplier to the item's parry block armor value to determine how much incoming damage is blocked if your parry attempt is successful. It does no damage but will usually stagger your enemy allowing you to follow up with whatever weapon you choose and your attack on a staggered enemy will deal 2x weapon damage.

Originally posted by Storm:

If you parry with a shield then the shield's parry bonus applies, not the knife's. The parry bonus is a multiplier to the item's parry block armor value to determine how much incoming damage is blocked if your parry attempt is successful. It does no damage but will usually stagger your enemy allowing you to follow up with whatever weapon you choose and your attack on a staggered enemy will deal 2x weapon damage.

Its x6 with the knife

So to clarify...

If I parry with a shield that has 2.5 parry damage, and use the knife immediately afterwards... I get 2.5 times the knife's damage.

If I parry with the knife and it has 4X parry damage, and immediately use the knife I get 4 times the knife's damage...

correct?

The stagger/stuned effect makes to apply backstab multiplier , thats its the same as parry bonus for blocking
So after all nope : knife have backstab x6 , thats the damage you will apply in a staggered monster
Parry bonus its for block armor that weapons and shields have when you parry an enemy to multiplier your block armor

Don't read 'parry bonus' as 'parry damage.' I think that's where the confusion is coming from.

'Parry' and 'damage' are two concepts that should not be conflated. No parry in this game inflicts damage. It's confusing, I know, but the parry bonus for an item helps calculate how much incoming damage from the enemy's attack you just parried gets blocked.

When you successfully parry with a shield or weapon, it often will stagger the enemy. While the enemy is staggered, you can do an attack that will inflict 2x the attacking weapon's primary attack value. Attacking a staggered enemy always does 2x damage with whichever weapon used in your attack.

To be clear, parrying will block more damage than a poorly timed block or just being in a defensive stance by holding down the right mouse button continuously. When successfully parrying, the Parry bonus of the shield or weapon used in the parry attempt applies to stop more incoming damage than you would have otherwise. The parry will also stagger the enemy, setting them up for a followup attack that will do 2x damage of whatever weapon you use in that attack.