Weapon Proficiency/Weapon Break

Weapon Break is a proficiency skill for 1H clubs in Sword Art Online: Integral Factor. It has a chance to activate a debuff on the enemy which decreases his Attack by 27% for 10 seconds. Upgrading this skill increases the chance to debuff the enemy (although the exact chances aren't stated in the skill's description).

The table below shows the level of the proficiency skill, prerequisites to level it up, and the materials required to level up the proficiency skill.