Shadow Strike costs less stamina, and when you use it while flanking an opponent, you reduce all of your active cooldown times.
Shadow Strike unlock
Quick Blade is a Rogue ability from the Subterfuge Tree in Dragon Age: Inquisition.
About Quick Blade
Quick Blade is an upgrade to Shadow Strike which reduces the stamina cost of the ability, and reduces all of your active cooldown times if used when flanking an opponent.
Notes and Tips
Subterfuge Ability Tree