Blade Echo?

[ExxeTrailblazer]

My Flicker tooltip says that if I crit or use Lightning Flash, I'd be ready for Blade Echo. I don't see this skill on my list at all, apart from the Awakened version. Am I missing something? Did I need to do a quest for it? Am I supposed to use one of those Hongmoon Technique thingies to learn it? Anyone wanna tell me anything about this? All I could get out of the net so far are outdated info from over a year ago or blade master's blade echo but I'm looking for Blade Dancer specific Blade Echo.

[Asuramon]

Blade echo is an "extra skill" (more like just extra damage honestly) that automatically triggers when you crit with flicker. Sunder has the same thing called shockwave.

 

Tl;Dr Flicker crits = Flicker crit damage + blade echo (even more damage)