Hi.
There is revised dev note regarding that skill here
https://ro.gnjoy.com/news/devnote/View.asp?category=3&seq=4179367&curpage=1
- 풍마수리검 - 구축
10레벨 기준 기본 공격력이 ATK 12600 +(장악Lv x00)%/ATK(폭발) 15600 +(장악Lv x300)%에서 ATK 15900 +(장악Lv x500)%/ATK(폭발) 18400 +(장악Lv x500)%로 증가됩니다. → (변경)10레벨 기준 기본 공격력이 ATK 12600 +(장악Lv x300)%/ATK(폭발) 15600 +(장악Lv x300)%에서 ATK 18400 +(장악Lv x1000)%/ATK(폭발) 18400 +(장악Lv x1000)%로 증가됩니다.
(추가)스킬 쿨타임이 1초에서 0.7초로 감소됩니다.
But I'll clarify how this skill works
The skill deal initial damage = 18400+(Huuma Shuriken - Grasp level x 1000)% on area,
But if there is hidden weapon zone, the skill will deal additional set of damage = 18400+(Huuma Shuriken - Grasp level x 1000)% as well
Here's skill description
https://www.divine-pride.net/database/skill/5484/huuma-shuriken-construct