Many Users of you have bugged characters and get "Parameter (4)" Error.
It happened because you was too fast in skilling.
You skilled a buged skill.
The 3rd book of Bicheon Cut series!
If you move with the cursor over the skill you will get also an error.
Please do not skill up this Skill!!!
The users with Bugged chars have to wait until we fixed that bug.
Hopefully it is done the next days.