Regarding the summoned NPCs and characters changed into Phantom

http://maplestory.nexon.net/news/news/current/00Fzq/

Due to a hack that allowed those who used it to eventually generate certain NPCs, several players turned into Phantom after clicking on a special, generated NPC then accepting a certain quest. It is important to know amidst some rumors in the community that this is the only way that characters were changing from a different job into Phantom. Clicking on a changed character will not change your own character.

The method the hackers were using has been blocked during this morning's maintenance, and the accounts of the hackers themselves are being dealt with.

In regard to the characters that were changed, we are investigating all of the details and hope to change all affected characters to their previous state next week. There are no plans for a rollback.