...results in a reduction of 53% on single targets, which also seems to be available for W/K and all the other /K classes, which is awesome!
I think it's calculated the other way. 100 patk * 0.68 (threaten) * 0.84 (Strik of Punishment). That will result in 43% reduction. I doubt the debuffs will be multiplied against each other. That would a unique mechanic that I've never saw in this game
Physical Attack and Physical Damage reductions applied to a NPC aren't behaving as you may expect. NPCs are losing excessive damage/attack than actual loss, and losing physical attack will also reduce physical damage of NPC too in a certain rate which we cannot share for now.
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