@ernilos OMG is my new and permanent nickname X'D
gmcon allows you to view the debug log, translation strings etc.. Tasty but useless, Yeah !
You can't use this command without a client patch, it is skipped by client if you aren't joined as staff member.. GM authentication changes the value of a boolean variable, find it.. Change the value to false/true (i don't remember the exactly value) and you have the access to it. Only who know reverse engineering will be able to unlock it. Good luck/fun.
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gmsg sets the daily family message, nothing to do with GM's commands..
Example: gmsg <PlayerID>|<Message>
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gmbr shows the family members list, nothing to do with GM's commands..
Example: gmbr 0 <PlayerID>|<A Long Number>|<Player Name>|<Player Level>|<Player Class>|0|9|<Online (0~1)>