Increases critical damage by 15%.

If Katar Mastery is at Level 10:
Enables the use of Double Attack Level 3.
(If a higher level of Double Attack is learnt, use that instead).

When equipped with Assassin Cross Stone II(Upper):
ATK + 5%. Increases critical damage by additional 15%.

When equipped with Assassin Cross Stone II(Mid):
Increases damage of Counter Slash by 20%.

When equipped with Assassin Cross Stone II(Lower):
Reduces after skill delay by 5%.

[iRO Description]
Increases critical damage by 15%, if learned Katar Mastery level 10, enables to use Double Attack level 3 (If user has higher level, that level will be triggered instead).
When equipped with Assassin Cross Stone II (Upper), Atk + 5%, increases critical damage by 15%.
When equipped with Assassin Cross Stone II (Middle), increases Counter Slash damage by 20%.
When equipped with Assassin Cross Stone II (Lower), reduces global cooldown by 5%