Though hopefully rare, during your adventures in the world of Defenders of the Cross you may come across a notification, typically in the form of an automated whisper message, that you or a character involved in an interaction you are taking part of has issued a NULL statement. This usually, though not always, causes the interaction to end and prevent the characters from continuing said event until the server reset (they can go elsewhere and try other interactions, it is just that one which will be blocked).
So what is a NULL statement? It is when your say something your character does not know (either because you are bringing out-of-game information into the conversation or you have not found it out with your character yet), you have made reference to something that does not exist within the DotC world (like accidentally pasting a website URL, yes it happens), or you find yourself in an area you are not supposed to have access to (such as a planet you do not have available transports to get to).
If you character receives too many NULL statements, consequences do exist. If you character reaches a threshold of NULL statements they will have their name revoked and be relegated to a “side character” with no identity. This can be seen as a player whose name is “D.####” where the #### stands for their ID number. Mistakes do happen from time to time, however, so it is only if your character receives too many NULL statements that this will happen. Furthermore over time, a character’s NULL count will be reset to zero, so doing your best to avoid these statements is enough to not have it affect your character.
How to avoid NULL statements?
Aside from the obvious part of avoiding accidentally posting website links or game commands in chat (like the /go or /ani commands) in the middle of a conversation, there are ways of keeping track of what your character knows and does not know. During various events, when your character obtains new knowledge or witnesses key events you will usually receive an announcement of You should remember this . . . alongside some experience points. This is letting you know that your character has learned of this information or event and may reference it in the future. There are also sources of information that your character can draw upon without having it confirmed through an interaction, these sources are your Clan Notices, Knowledge Base Articles, Correspondence / Books, and Announcements that have gone off in-game.