Zen Archer Windpiercer spec bug

[C1nd3rS0ul]

First of all I don't know if this is a bug or that's how is intended to be, but there's a skill or passive or something called 'Cloud Catcher' that does damage but doesn't really count as your damage and this skill/passive is 10-11% of your damage. I'm the only one attacking this enemy and my damage counted for 89,33%.