I have feeling only me have so much problems with KA...
several boss events my avatar after hitting boss then swinging with sword about 30-45 sec. It really very pissed when u have no time on that sh...
It happened on diffrent Internet conections: on several 3G, on several fast Wi-Fi (at work, at home, at public places), so it is not bad connection issue.
I tried reinstalled the game, nothing helped.