Here's a copy-paste of a thread I made on the Nexon forums/ticket I submitted.
"Yesterday I went into Knight Stronghold: Cygnus Garden and was promptly disconnected with no error screen.
After relogging, the same thing happened several times until I gave up.
After the patch, I thought that dc hacking would have eased up, but it has just gotten worse.
There are now characters somehow chatting in your expedition chat with spam so fast that it lags and eventually disconnects you.
Of course, the hacker(s) have a reason to do this. Kaisers seem to be able to use the "stack hack" again, which was what allowed low level, unequipped kaisers to solo empress before. This went on for weeks or months and was recently stopped. Now it is back again and it seems one or a few persons are completely regulating Cygnus Chamber and disallowing legitimate players entrance or a chance of killing this boss or her minions. I have several igns that were being used that I can provide. Two for DC hacking, and several igns of level 17x kaisers that are poorly outfitted and yet fully soloing Empress while mysteriously not being targeted by this DC hacker.
I hope something can be done about this. Simply leaving a GM to check in the room every half hour or so would suffice. Just a glance at the monitor can show whether a player is legitimate or using stacking skill effects on an illegitimate character. If not that, I hope that Nexon can do something about the base, the hacks themselves, so that normal legitimate characters can enjoy the game instead of being blocked completely from certain aspects of it."